The verdict in three sentences
A well-built B2B online payment flow cuts collection delays by 15 to 40 days and makes reconciliation reliable. The real cost is not the headline commission but the total cost of ownership: variable fees, fixed per-transaction fees, integration and maintenance. In London in 2026, a B2B SME integrates a modern PSP for 4,000 to 15,000 EUR depending on the level of customization.
What a PSP actually costs in 2026
Payment service providers (PSPs) charge a variable commission plus a fixed fee per transaction. For high-ticket B2B, the fixed fee matters little; the percentage is what counts. Here is a 2026 order of magnitude for the European market.
| PSP | Card commission | Fixed fee / txn | SEPA transfer | Integration |
|---|---|---|---|---|
| Stripe | 1.5 % + 0.25 EUR | 0.25 EUR | yes (0.80 EUR) | 4,000-12,000 EUR |
| Mollie | 1.8 % + 0.25 EUR | 0.25 EUR | yes | 3,500-10,000 EUR |
| Stancer | 1.4 % + 0.25 EUR | 0.25 EUR | yes | 4,000-9,000 EUR |
| GoCardless (SEPA) | 0.35 % + 0.20 EUR | capped 2.50 EUR | direct debit | 5,000-15,000 EUR |
| Adyen | 1.6 % + 0.11 EUR | 0.11 EUR | yes | 8,000-20,000 EUR |
For an average B2B basket of 1,800 EUR, a 1.5 % commission is 27 EUR; via GoCardless SEPA direct debit capped at 2.50 EUR, the gap is huge on recurring flows.
The integration cost line items
Beyond commission, technical integration concentrates the project budget. Here is a typical breakdown for a London build.
| Line item | Content | 2026 order of magnitude |
|---|---|---|
| PSP integration | API, tokenization, 3-D Secure v2 | 2,500-6,000 EUR |
| Reconciliation | Auto matching orders / payments | 1,500-4,000 EUR |
| Multi-method | Cards + SEPA + transfer + BNPL | 1,500-3,500 EUR |
| Back-office | Refunds, disputes, accounting exports | 1,000-3,000 EUR |
| Testing & compliance | 3-D Secure, PCI-DSS SAQ-A, UAT | 1,000-2,500 EUR |
3-D Secure v2 is mandatory in Europe (PSD2); it adds an authentication step but cuts unpaid invoices and disputes by more than 60 %.
Mini case study
Claire, CFO of a B2B trading SME in London (revenue 6 M EUR, 900 invoices/year, average basket 1,800 EUR). Before: 100 % manual bank transfer, average collection delay 52 days. She integrates Stripe (cards + SEPA) for 9,000 EUR. New average delay: 28 days, freeing 24 days of cash on 1.6 M EUR of receivables, roughly 105,000 EUR of working capital recovered. Commission cost: 1.5 % on 40 % of flows shifted to cards, ~14,400 EUR/year, easily offset by the cash gain and fewer chasers.
Need a professional website?
Kolonell builds websites that attract clients, optimized for the Sénégalese market. Free quote in 2 minutes.
FAQ
What is a realistic budget to integrate B2B online payments in 2026?
Expect 4,000 to 15,000 EUR for integration depending on payment methods and back-office. Multi-method projects with advanced reconciliation trend toward the top of the range.
Should B2B favor SEPA direct debit or cards?
For recurring B2B, SEPA direct debit (GoCardless at 0.35 % capped 2.50 EUR) is far cheaper than cards on large baskets. Cards remain useful for new customers and one-off payments.
How long does integration take?
Between 3 and 6 weeks depending on complexity: a single card PSP can ship in 3 weeks, while a multi-method integration with reconciliation and accounting exports needs 5 to 6 weeks.
Does 3-D Secure hurt conversion?
The v2 version is smooth (frictionless authentication in 70 to 90 % of cases). The slight dip is more than offset by fewer unpaid invoices and disputes.
Can we switch PSP later without rebuilding everything?
Yes, if the integration goes through an abstraction layer. This is an architecture choice to set from day one to avoid vendor lock-in.
Let's scope your project. Tell us your invoice volume, average basket and target payment methods, and we will cost the most profitable PSP integration. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.
Mohamed Bah
Fondateur, Kolonell
Passionate about digital and entrepreneurship in Africa, Mohamed has been helping Sénégalese businesses with their digital transformation since 2020. Founder of Kolonell, he believes every SME deserves a professional and accessible online présence.
