What are the three types of payment systems?

The three main types of payment systems are: Card-based systems – including credit and debit card payments processed through banks and card networks. Digital and mobile payments – such as e-wallets, contactless payments, QR code payments, and crypto payments. Bank transfer systems – including direct transfers, ACH, SEPA, and other bank-to-bank payment processing options. Businesses often combine various payment methods to meet market demands and support cross–border payments while maintaining a secure environment. Many modern payment systems also support omnichannel payments, allowing customers to complete transactions through in-store POS terminals, websites, and mobile apps.

How does payment processing software work?

Payment processing software manages the whole transaction lifecycle: from the customer submitting payment details to final authorization and settlement. The system securely transmits card data to the acquiring bank and other financial institutions, reserves funds once approved, and later settles them into the merchant’s account. Around that core flow, it must support cards, digital wallets, bank transfers, and other methods in a single ledger, apply PCI DSS controls wherever it handles cardholder data, and meet the frameworks for the markets it serves, such as 3D Secure, SOX, and GDPR.

What is an example of a PSP?

Adyen, Stripe, and PayPal are the most recognizable payment service providers. A PSP lets a business accept payments without holding its own merchant account or signing acquirer contracts, bundling the gateway, processing, and often acquiring with merchant onboarding, risk screening, and settlement reporting. Becoming a payment processor in your own right works the other way, since it requires acquirer sponsorship, card network registration, PCI DSS validation, and your own settlement and ledger stack. Platforms usually start building their own payment software at that point.

What is the difference between payment software and a payment gateway?

A payment gateway handles one stage: collecting payment data at checkout and routing it to a processor for authorization. Payment software is the wider system the gateway sits inside, covering processing and settlement, merchant onboarding, billing, payouts, reconciliation, reporting, and risk. The two are scoped and quoted as separate projects, so payment gateway development can ship on its own while the platform around it follows. A company can buy a gateway and still have no way to onboard a merchant, make a payout, or close its books.

What are the four types of payment gateways?

The four primary types of payment gateways are: Hosted gateways : customers are redirected to a third-party provider’s secure page to complete payment. Self-hosted gateways : payment data is collected on your site and sent to the gateway for authorization. API-based (integrated) gateways : allow seamless integration directly into your platform for a fully branded checkout experience. Local bank integration gateways : direct connections with financial institutions for region-specific processing Choosing between a third-party gateway and custom payment gateway development depends on your scalability needs, transaction costs, compliance requirements, and long-term growth strategy.

How long does payment software development take?

The timeframes for payment software development will vary based on a number of factors, including scope, compliance, and integration. Payment solutions that include a single PSP integration and checkout will take 3–6 months to develop. A fully featured payment platform with its own gateway, payment processing capabilities, fraud detection, merchant onboarding, and multi-currency support will take 9–18 months to develop. Acquirer and card network certifications can add another 3–6 months and should be planned from the start. At SPD Technology, we delivered a complete payment solution for Poynt in 5 months .

What factors determine the cost of payment software development?

The biggest cost drivers are scope, compliance requirements, integrations, and fraud prevention capabilities. A single PSP integration costs significantly less than building a custom gateway with its own payment processing engine. PCI DSS requirements, acquirer integrations, and advanced fraud detection features can also increase development effort. The best way to estimate costs is to run a discovery phase that defines requirements, integrations, and transaction-volume targets. At SPD Technology, we provide estimates based on a discovery process that evaluates these factors before development begins.

What security and compliance standards apply to custom payment software?

Compliance requirements depend on the payment model, markets served, and types of transactions processed. The primary standard is PCI DSS, which applies to systems that store, process, or transmit cardholder data. Additional requirements may include GDPR, AML, 3D Secure, and OFAC screening. PA-DSS was retired in October 2022 and replaced by the PCI Secure Software Standard, so payment applications are now validated under the PCI Software Security Framework. Building these requirements into the architecture from the start reduces risk and avoids costly changes later.

Payment Software Development for PSPs and Platforms

SPD Technology has worked in payment software development since 2006, building the platforms that payment service providers, PayFacs, marketplaces, and fintech products run their money through. That work covers processing and settlement, orchestration across multiple PSPs, marketplace payouts, merchant onboarding, billing, and POS, so platforms can add acquirers and payment methods without rebuilding their core.

SPD Technology
Payment Software Development for PSPs and Platforms

Looking for Payment Software Development?

Most teams reach us at one of two moments: either when a single gateway integration no longer matches the business model, or when a platform already in production cannot keep up with volume, a new acquirer, or a new compliance deadline. Our payment solution software development starts with your business model, so the architecture reflects how money actually moves between your platform, your merchants, and your acquirers.

We also work to tight deadlines. For Poynt, we delivered an all-in-one payment platform in 5 months, with 8 areas of scope in the first release:

Gateway and processor integration, including acquirer certification
Tokenization, encryption, and PCI DSS scope reduction
Invoicing, subscriptions, and usage-based billing
iOS and Android apps with virtual terminal and wallet support
Merchant dashboards and checkout UX
POS terminal integration for card-present channels
Multi-currency pricing, settlement, and reporting
Risk scoring, AML pattern detection, and chargeback handling

That range comes from years of fintech software development services, where the same teams build, certify, and operate what they ship. Engagements can start as small as a single integration and grow into payment platform software development services that take a product from discovery through acquirer certification to live operations.

When a platform already exists, software modernization is often faster, since replacing a settlement engine or risk layer inside a working system costs less than rebuilding the product around it.

Where Payment Platforms Break at Scale

Most production failures in payment platforms show up in the seams between components, where a gateway, an acquirer, a risk engine, and a ledger each behave correctly on their own and still disagree about what happened to a transaction. Four of those seams account for most of the work we are called into.

Settlement That Cannot Keep Up
Processors report money movement differently, some in end-of-day batches and some as event streams, so a settlement engine built for one starts duplicating records when the second arrives. At Poynt, we redesigned settlement around Adyen’s event model and extended it to PayFac sub-merchants, so funds split across a hierarchy still reconcile to one ledger.
Single-PSP Dependency
Routing everything through one provider makes that provider’s downtime your downtime, and puts acquirer volume commitments at risk whenever approval rates dip. For Axcess Payment Services, a UK PSP, rules-driven routing follows per-merchant rules, card attributes, and acquirer volume commitments, so new partners go live through configuration instead of a release.
Retries That Double-Charge
A timeout tells the caller nothing about whether the payment went through, so a client that retries against a non-idempotent API can charge the same card twice. Idempotency keys make the repeated request return the original result, and reconciliation matches every authorization to its capture, refund, or reversal, which also feeds fraud detection software development.
Incidents at Three in the Morning
Payment incidents arrive at any hour, and a distributed team loses most of its response time to paging, gathering context, and tracking down whoever last touched the service. For a US cashback fintech, we built Incident Pilot, an AI agent that reads the alert and the codebase and opens a PR-ready fix about 24 minutes after detection, down from more than 60 minutes.

Our Payment Software Development Services

Our payment software development services cover gateways, processing, POS, billing automation, and merchant onboarding, with compliance first. We also offer post-release services such as maintenance, certification updates, and payment type updates. As an official Adyen service partner, we also provide Adyen integration services.

Payment Gateway Development
A custom gateway gives you control over pricing, routing, and reporting that hosted checkout cannot. Our custom payment gateway development covers the authorization path, tokenization that keeps cardholder data out of PCI DSS scope, asynchronous settlement, and load balancing across acquirers, so one provider’s outage leaves the rest of your traffic flowing.
Payment Gateway Integration
Connecting to someone else’s gateway gets harder with each one added, since error semantics differ from provider to provider. Our payment gateway integration services cover direct post, hosted, and API-based methods, so merchants see consistent behavior whichever provider handles the transaction. For NimbleCommerce, we brought 27 payment systems behind one interface, so one provider’s outage leaves the rest of your traffic flowing.
Payment Processing Software Development
Volume shows up first in processing. We implement event-based transaction processing, asynchronous settlement, and continuous reconciliation with idempotent retries on timeout. Our experts develop payment processing software for cards, bank transfers, P2P, prepaid, gift cards, and wallets on one ledger, then extend it through alternative payment methods development.
Payment Application Development
A payment app usually has to do much more than take a checkout. In mobile payment app development, we ship iOS and Android products with virtual terminals for phone orders, invoicing, wallet support, loyalty programs, and merchant cash advances, built so that one set of APIs serves the app, the merchant dashboard, and the card terminal in the same way.
POS Software Development
PCI DSS also has specific scope and restrictions for card-present transactions. Our POS software development services include terminal bundles for Android terminals, contactless and QR payments, automatic transaction capture, receipt printing, and inventory synchronization between in-store and online purchases, with offline mode defined in advance.
Billing Software Development
Billing problems tend to surface at renewal, long after the code that caused them shipped. Our billing software development handles subscriptions, usage-based pricing, and tiered plans, with automated invoicing, payment reminders, and account reconciliation. On the omnicommerce platform we built, multi-currency invoicing and recurring payments run on that same engine.
Payment Orchestration Platform Development
Orchestration changes routing from code changes to configuration changes. Our payment orchestration platform development routes based on each merchant’s rules, card characteristics, and acquirer volume commitments; it screens risks before authorizations and runs on a PCI DSS v4.0.1-compliant core, as in the case of Axcess Payment Services, a UK PSP.
Merchant Onboarding and KYC Development
Onboarding sets the pace for how fast a platform can grow. Our merchant onboarding solutions automate identity document checks, OFAC screening, EIN and SSN verification, beneficial ownership checks, and risk scoring. For Blackhawk Network, that work took onboarding from seven days to under 24 hours and brought on 8,000 US businesses within two years.

Value-Based Outcomes We Delivered to Our Global Clients

SPD Technology helps payment providers, marketplaces, and digital platforms modernize payment infrastructure, shorten onboarding, and scale transaction processing. Every figure below comes from a case study you can check.

→ 5-Month Omnicommerce Platform Delivery
Delivered an all-in-one payment solution with gateway, processing, billing, POS, and risk management capabilities in just five months.
See Case Study
→ PayFac Model Successfully Launched
Helped transform a payment processing service into a PayFac platform with scalable merchant onboarding and payment operations.
See Case Study
→ 7× Faster Merchant Onboarding
Automated KYC, OFAC, EIN, and SSN verification workflows reduced merchant onboarding time from 7 days to less than 24 hours.
See Case Study
→ 8,000+ Businesses Aggregated in 2 Years
Developed a merchant portal that enabled the onboarding and management of more than 8,000 US businesses.
See Case Study
→ 80%+ AI Eligibility Accuracy
Automatically classified product eligibility for FSA and HSA payments, with release cycles under a day and HIPAA and SOC 2 controls in place.
See Case Study
→ ~24 Minutes to a PR-Ready Fix
From production incident to PR-ready fix for a US cashback fintech, with 24/7 coverage and an engineer approving each change.
See Case Study

Why Choose SPD Technology for Payment Software Development

Payment work is judged on what survives in production. These eight points are the ones our clients can check against a live system or a case study.

Long-Running Platform Ownership
We stayed with Poynt for more than five years, from the first release through PayFac settlement and processor changes, providing Level 3 support and production monitoring the whole time. Owning a payment platform that long changes how you build it, because every shortcut comes back to the same team.
Processor and Acquirer Integration
Certification is where payment projects usually lose their schedule. At Poynt, we integrated and certified Adyen as a processor and handled Elavon upgrades; for NimbleCommerce, we connected 27 payment systems. We plan certification windows based on experience rather than a vendor’s estimate.
PayFac Settlement Architecture
Becoming a payment facilitator changes settlement, liability, and reporting at once. Our PayFac platform development covers hierarchical sub-merchant settlement, split payments, and fee management, with billing that handles subscription, usage-based, and tiered plans on the same engine.
Compliance Set in Discovery
PCI DSS scope is a design decision, so we set it during discovery rather than at the audit. For the FSA and HSA payments product, we implemented HIPAA and SOC 2 controls with Vanta, which kept release cycles under a day while the evidence collection ran continuously in the background.
Merchant Onboarding and KYC
Blackhawk Network needed identity and sanctions checks that met US requirements without adding days to activation. We automated OFAC screening, EIN and SSN verification, and the approval workflow around them. The same patterns run in the merchant risk management software that scores accounts once they are live.
AI Applied to Payments
AI fits payments best where volume is too high for manual review. Our AI/ML development services classified FSA and HSA product eligibility at over 80% accuracy. Incident Pilot, the agent we built for a cashback fintech, drafts production fixes with an engineer approving each one.
Official Adyen Service Partner
Adyen lists SPD Technology as a service partner for product engineering and integration work across POS, web, mobile, and API-first platforms. SPD Technology is also an AWS Select Tier Services Partner, which covers the cloud side of the same builds. Our Adyen integration services build on work the team has already certified in production.
Transparent Delivery and Estimates
We estimate only after a discovery phase, so the figure reflects the integrations and compliance scope we find rather than an average. The agreement sets out intellectual property rights, milestone-based reporting, and one team staying with the product after launch.

Find out where AI can take load off your payment operations: from eligibility checks to incident response.

Our Payment Software Development Process

Payment platforms are built once and certified repeatedly, so our payment software development services front-load compliance and leave evidence behind at every step.

01 · Discovery and Compliance Scoping
Every project starts with your business model, transaction flows, and regulatory obligations. We define PCI DSS, AML, and GDPR requirements up front, so architectural decisions carry their compliance consequences from day one.
You get: a compliance scope document, architecture recommendations, and build-versus-integrate guidance for each component of the platform.
02 · Architecture and Technology Selection
From there, our architects design the gateway and processing layers, tokenization strategy, settlement workflows, fraud integration points, and redundancy mechanisms, drawing on the same practice as our payment system architecture consulting.
You get: architecture and data flow diagrams, a technology decision record, and agreed non-functional targets for throughput, latency, and availability.
03 · Iterative and Security-First Development
Development runs in sprints with compliance requirements embedded in each one. Payment integrations, encryption controls, access policies, and transaction workflows are validated in controlled environments before anything reaches production.
You get: a working increment in staging, a security test report, and an updated PCI DSS control mapping you can hand to an assessor.
04 · Testing, Certification, and Validation
Before launch, we validate transaction flows, performance, and security through end-to-end and load testing, then support the certification work with payment providers, acquirers, and card networks. Having run Adyen and Elavon certifications in production, we know which evidence each party asks for.
You get: test results, a load test report, and a certification evidence pack.
05 · Launch, Monitoring, and Maintenance
Launch starts the longest phase, which runs through monitoring, maintenance, compliance updates, and payment method expansion.
You get: runbooks, monitoring dashboards with alerting, a support model with agreed response times by severity, and a release cadence that keeps certification evidence current as acquirers change.

Trusted Globally by Innovation-Driving Companies

From Fintech industry stalwarts to industry-leading eCommerce providers, we ensure the comprehensive alignment between emerging technologies and established business processes.

An American financial services firm that provides investment research and investment management services
Financial data and software company with offices in London, New York, San Francisco, and Seattle.
All-in-one omni commerce payment solution with contactless, fast, secure, and safe payment processing
One of the most recognizable landmarks, a company that specializes in innovative travel and hospitality services
SaaS XSPN – Next Generation Application & Cloud Security Posture Management
A leading tech-enabled insurance company that provides workers’ comp coverage to small businesses
A UK-based provider of online payment solutions to businesses of all sizes worldwide

Success Stories with Global Impact

SPD Technology designs and develops transformative software solutions that drive innovation, new revenue streams, and market leadership.

See All Cases

Powering Poynt’s Growth with Scalable Payment Infrastructure

Industry: Finance, Payments & Fintech
Country: USA
Team Size: 10

Successful and Ongoing Collaboration with Poynt: successful and long-term collaboration has resulted in multiple successful projects, including the rapid development of an all-in-one omnicommerce payment system and resulted in an acquisition by a global tech company.
Payment Processing Expertise at Scale: developed a set of cutting-edge back-end services with an API interface responsible for a full cycle of payment processing, settlement, and integration with 3rd party payment partners.

View Case Study

Developing an Aggregated Merchant Portal for Global Gift Card Distribution

Industry: eCommerce & Retail, Finance, Payments & Fintech
Country: USA
Team Size: 10

Merchant Portal That Aggregates 8000 Businesses in the US: the successful development and deployment of the Merchant Portal facilitated the aggregation of over 8000 businesses within the United States in just two years.
7x Merchant Onboarding Time Reduction: resulted in an impressive efficiency gain and decreased operational costs for the business as manual onboarding efforts are significantly reduced.

View Case Study

How We Helped FSA/HSA Payments Company to Improve Existing Product

Industry: Finance, Payments & Fintech
Country: USA
Team Size: 2

Less-Than-1-Day Release Cycles: Implementation of the serverless infrastructure and fast CI/CD pipelines that were configured by our team resulted in short release cycles, which is critical for a startup.
80%+ Accuracy of Our AI Solution: Achieved an impressive percentage of success in determining the eligibility of health-related products in our fully automated solution.

View Case Study

About
SPD Technology

SPD Technology is a global software product development company founded in 2006, with delivery centers across Europe and 650+ specialists.

From MVPs through to large production systems, we work in fintech and digital payments, data engineering, AI and ML, and cloud. Payments is one of our longest-running practices.

We have delivered more than 460 custom projects for startups, SMBs, and enterprises, and work with PitchBook, Morningstar, Blackhawk Network, Poynt, and Space Needle.

Get an architect to review your payment platform before the next acquirer, market, or compliance deadline.

Engagement Models

Addressing All Your Payment Software Development Requirements

Tell Us About Your Project

Team Extension (Staff Augmentation)
Team extension is often the beginning of a lot more meaningful business relationships. rnrnAs we are aware of this, we provide Team Extension services to quickly extend your in-house team with one or more experts (usually, 1-3 persons) in order to beef it up or fill an expertise gap
Self-Managed Team (Dedicated Team)
The Managed Team engagement model allows you to expand your in-house team in a more significant way than under Team Extension: we hand-pick several experts in accordance with your requirements to create a self-managed development team that is run by one of our seasoned Project Managers
Project-Based Outsourcing Services
Under Project-Based Outsourcing, our team assumes full responsibility for implementing the entirety of your project: we provide all the various experts required during the Discovery/Business Analysis, Development, QA Testing, and, possibly, Support Maintenance phases

Certified

By Independent Organizations

Helping global businesses implement Adyen payment solutions with secure architecture and optimized transaction flows.

Confirmed by Oracle certification, our company provides top-notch tech expertise in building and delivering cutting-edge database and cloud-based apps.

IIBA Certification signifies our proficiency in business analysis, ensuring a deep understanding of client needs and industry requirements.rn

With AWS Certification, we guarantee top-tier cloud expertise, enabling us to architect robust, scalable, and secure solutions.

Trusting your project development to us, you can rely on our project management excellence, meticulous planning, and efficient resource utilization. rn

Our Scrum Alliance Certification demonstrates our dedication to agile methodologies, fostering collaboration and iterative development.rn

Backed by Scrum.org Certification, our development team leverages the best principles of Scrum to build superior and iterative software solutions.

FAQ

Answering common questions about payment software development.

What are the three types of payment systems?
The three main types of payment systems are:
- Card-based systems – including credit and debit card payments processed through banks and card networks.
- Digital and mobile payments – such as e-wallets, contactless payments, QR code payments, and crypto payments.
- Bank transfer systems – including direct transfers, ACH, SEPA, and other bank-to-bank payment processing options.
Businesses often combine various payment methods to meet market demands and support cross–border payments while maintaining a secure environment. Many modern payment systems also support omnichannel payments, allowing customers to complete transactions through in-store POS terminals, websites, and mobile apps.
How does payment processing software work?
Payment processing software manages the whole transaction lifecycle: from the customer submitting payment details to final authorization and settlement. The system securely transmits card data to the acquiring bank and other financial institutions, reserves funds once approved, and later settles them into the merchant’s account.
Around that core flow, it must support cards, digital wallets, bank transfers, and other methods in a single ledger, apply PCI DSS controls wherever it handles cardholder data, and meet the frameworks for the markets it serves, such as 3D Secure, SOX, and GDPR.
What is an example of a PSP?
Adyen, Stripe, and PayPal are the most recognizable payment service providers. A PSP lets a business accept payments without holding its own merchant account or signing acquirer contracts, bundling the gateway, processing, and often acquiring with merchant onboarding, risk screening, and settlement reporting.
Becoming a payment processor in your own right works the other way, since it requires acquirer sponsorship, card network registration, PCI DSS validation, and your own settlement and ledger stack. Platforms usually start building their own payment software at that point.
What is the difference between payment software and a payment gateway?
A payment gateway handles one stage: collecting payment data at checkout and routing it to a processor for authorization. Payment software is the wider system the gateway sits inside, covering processing and settlement, merchant onboarding, billing, payouts, reconciliation, reporting, and risk.
The two are scoped and quoted as separate projects, so payment gateway development can ship on its own while the platform around it follows. A company can buy a gateway and still have no way to onboard a merchant, make a payout, or close its books.
What are the four types of payment gateways?
The four primary types of payment gateways are:
1. Hosted gateways: customers are redirected to a third-party provider’s secure page to complete payment.
2. Self-hosted gateways: payment data is collected on your site and sent to the gateway for authorization.
3. API-based (integrated) gateways: allow seamless integration directly into your platform for a fully branded checkout experience.
4. Local bank integration gateways: direct connections with financial institutions for region-specific processing
Choosing between a third-party gateway and custom payment gateway development depends on your scalability needs, transaction costs, compliance requirements, and long-term growth strategy.
How long does payment software development take?
The timeframes for payment software development will vary based on a number of factors, including scope, compliance, and integration. Payment solutions that include a single PSP integration and checkout will take 3–6 months to develop. A fully featured payment platform with its own gateway, payment processing capabilities, fraud detection, merchant onboarding, and multi-currency support will take 9–18 months to develop.
Acquirer and card network certifications can add another 3–6 months and should be planned from the start. At SPD Technology, we delivered a complete payment solution for Poynt in 5 months.
What factors determine the cost of payment software development?
The biggest cost drivers are scope, compliance requirements, integrations, and fraud prevention capabilities. A single PSP integration costs significantly less than building a custom gateway with its own payment processing engine. PCI DSS requirements, acquirer integrations, and advanced fraud detection features can also increase development effort.
The best way to estimate costs is to run a discovery phase that defines requirements, integrations, and transaction-volume targets. At SPD Technology, we provide estimates based on a discovery process that evaluates these factors before development begins.
What security and compliance standards apply to custom payment software?
Compliance requirements depend on the payment model, markets served, and types of transactions processed. The primary standard is PCI DSS, which applies to systems that store, process, or transmit cardholder data. Additional requirements may include GDPR, AML, 3D Secure, and OFAC screening. PA-DSS was retired in October 2022 and replaced by the PCI Secure Software Standard, so payment applications are now validated under the PCI Software Security Framework. Building these requirements into the architecture from the start reduces risk and avoids costly changes later.