What Does It Cost to Integrate Payments?
A payment integration typically costs SEK 100,000–400,000 to build, depending on the number of payment methods and how the flow connects with orders, receipts, and accounting. Transaction fees to the provider come on top, often a fixed fee per purchase or a percentage of the amount. Card data should always be handled by a certified provider.
A payment integration has two price tags: a one-time cost to build the flow and an ongoing transaction cost that follows every purchase. The first shows up in the proposal, the second determines profitability as volume grows. Here are both – plus the security requirements that determine whether you’re even allowed to handle card data.
The pricing picture: SEK 100,000–400,000 in implementation
Integrating payments with an established provider like Stripe, Klarna, or Swish typically costs SEK 100,000–400,000, depending on scope:
| Scope | Typical cost |
|---|---|
| One payment method, simple purchase flow | SEK 100,000–180,000 |
| Multiple payment methods, receipts, and refunds | SEK 150,000–280,000 |
| Subscriptions, saved payment methods, and accounting connection | SEK 250,000–400,000 |
What drives the cost is rarely the payment moment itself – the providers’ ready-made components make that part easy. It gets more expensive around it: refunds, failed payments, subscription logic, receipt handling, and reconciliation against the accounting system.
The transaction fees: comparison
On top of the build, you pay per transaction. The rates are negotiated and change – treat them as orders of magnitude and always check the current price list and your own agreement:
| Payment method | Approximate transaction cost | Comment |
|---|---|---|
| Card payment (e.g. via Stripe) | About 1.5–3% + a fixed fee per purchase | Depends on card type and region; European cards cheapest |
| Klarna | Fixed fee + variable share per purchase | Varies with payment method (invoice, installment, direct) and agreement |
| Swish Handel | Fixed fee per transaction, often a couple of kronor | Set by your bank; a connection fee may apply |
The pattern matters more than exact figures: percentage-based fees favor low average amounts, fixed fees favor high ones. A service selling at SEK 49 per purchase and one selling at SEK 4,900 should therefore work out entirely different payment mixes.
PCI DSS: why you should never touch card data yourself
PCI DSS is the card industry’s security standard, and the required level is governed by how card data flows through your solution. If you use the payment provider’s ready-made payment components – where the card number is entered into the provider’s interface and never passes through your servers – you land on the simplest self-assessment level. If you build your own forms that receive card numbers, or store card data in your own systems, you step into extensive certification requirements with annual audits that cost many times more than the whole integration.
The conclusion is simple and applies to nearly everyone: let a certified provider handle the card data. You get a modern payment experience, avoid the certification burden, and don’t carry the risk of the worst-case scenario – leaked card details.
Worked example: an online store adds cards and Swish
An online store builds a checkout with card payment and Swish, including refunds and receipts. Implementation takes about five weeks: SEK 180,000–240,000. At 2,000 purchases a month with an average value of SEK 500, the card fees come to roughly SEK 15,000–30,000 a month if everyone pays by card. After a bit over a year, the transaction fees have surpassed the build cost – which is entirely normal, but shows where negotiating power should be applied once volume has grown. If the store later wants to add Klarna, that adds a few weeks of work; more payment methods are cheapest to plan in at the initial build.
The cost traps to watch out for
The build cost is rarely what makes payment projects expensive in the long run – it’s the items that weren’t in the proposal:
- Subscriptions get underestimated. Recurring payments sound simple but bring along failed charges, card updates, reminders, and cancellation flows – often half the integration work.
- Refunds and disputes get forgotten. The flows for refunds and chargebacks have to be both built and staffed, otherwise every case becomes manual work.
- Reconciliation gets postponed. Without an automatic connection to the accounting system, the manual work grows with every month’s volume.
- The fees never get renegotiated. The terms that applied at launch are rarely right at ten times the volume – schedule an annual review.
Think about the whole picture from the start
The cheapest payment integrations are the ones designed together with the order flow and accounting from the start: what happens on an abandoned purchase, how are payouts recorded, who handles disputes? At Weapp we build payment flows as part of web and app development, and it’s almost always the whole picture – not the payment button – that determines the cost. Want a range for your solution? Get in touch.
Frequently asked questions
Which payment provider is cheapest?
It depends on volume, average order value, and payment mix. Percentage-based fees favor low amounts, fixed per-unit fees favor high ones. Compare the total annual cost in your own calculation – transaction fees, monthly fees, and development cost – instead of fixating on a single percentage, and renegotiate as volume grows.
What is PCI DSS?
PCI DSS is the card industry's security standard for anyone handling card data. The required level depends on how the card details flow: whoever uses the payment provider's ready-made components lands on the simplest self-assessment level, while whoever receives or stores card data themselves faces extensive and costly certification requirements.
Can you switch payment providers later?
Yes, but the move is rarely free. The integration itself can be rebuilt, but saved payment methods and ongoing subscriptions are tied to the provider and can be difficult to migrate. Factor in the exit scenario already at the selection stage, especially if the service relies on recurring payments.
How long does a payment integration take?
A simple purchase flow with a provider's ready-made checkout takes 3–5 weeks including testing. Multiple payment methods, refunds, and a connection to the accounting system push it closer to 6–8 weeks. Testing is a large share of that – payment flows need to be tested for abandoned purchases, declined cards, and duplicates, not just the happy path.
Why should payments be connected to the accounting system?
Because the payouts from the payment provider arrive in batches, with fees already deducted, and need to be reconciled against individual orders. Without automatic reconciliation, the manual work grows with volume and errors get caught late. That connection is often the most underestimated part of a payment integration.