A payments company bills for money moving, which makes its invoice the hardest in B2B. The price is a percentage of someone else's transaction, it has a minimum and a maximum, it differs by country and payment method, and there are 40 million of those transactions a month. This guide explains the mechanics first and names vendors second.

Vendor facts are as of October 2026 and link to each vendor's own page.

What's different about billing for fintech and payments

The price is a percentage with a floor and a cap

SaaS billing multiplies a quantity by a price. Payments billing takes a percentage of an amount, then applies a minimum and a maximum per transaction. A fee of 0.9% with a €0.10 floor and a €5 cap charges €0.10 on a €5 payment, €0.90 on a €100 payment and €5 on a €2,000 payment. The billing system has to do that per event. Doing it on the monthly total gives a different, wrong answer.

Fees are nested

Rates depend on properties of the transaction: region, payment method, card type, sometimes merchant category. A merchant contract might say 2.9% for EU transactions, 0.2% for EU bank transfers and 3.4% for EU credit cards. Written flat, that's a rule for every combination, and the list grows with each new market. Written nested, it's a parent rate with exceptions beneath it, and the most specific match wins.

Volume is per transaction

A mid-sized processor generates tens of millions of billable events a month. Each one carries an amount and 4 or 5 properties that affect the price. Pre-aggregating before rating loses the per-transaction floor and cap.

An example deal

A merchant signs with a payments provider on these terms:

• 1.4% + €0.10 on EU consumer cards, with a €0.25 minimum per transaction

• €0.20 flat on SEPA Direct Debit

• a €1,500 monthly minimum across all fees

• volume tiers that step the card rate down above €2M a month

• invoiced from the Dutch entity in euros and the UK entity in pounds

That's one ordinary contract. A provider with 300 merchants has 300 of them, each a little different.

Entities and procurement

Fintechs hold licences per jurisdiction, so they invoice from several legal entities with separate tax registrations and invoice numbering. European e-invoicing mandates apply entity by entity. And the buyers are often banks, whose procurement asks for data residency and audit trails before a pilot.

Where subscription billing breaks

A subscription system expects a plan and a quantity. It can usually take a usage number per month. It struggles with a percentage of a monetary amount per event, and with a floor that applies per transaction and a minimum that applies per invoice at the same time. Teams bridge the gap by computing fees in a data warehouse and uploading totals, and then the invoice can't be explained line by line when a merchant disputes it.

Evaluation criteria

Score each vendor from 0 to 5 and multiply by the weight. Change the weights to suit your business.

The shortlist

Solvimon

Solvimon is billing infrastructure built by the team that ran billing inside Adyen, and it powers some of Europe's largest fintechs. It fits processors, open banking platforms and fintech infrastructure with percentage fees, nested pricing rules by region and method, and several legal entities. It's more than a single-product fintech on flat plans needs. Published price: Growth from $2,500 a month (pricing). Yapily, with €39.5B in annual payment volume, automated 98% of invoicing across 200+ bespoke plans (case study).

Sequence

Sequence is contract billing with AI intake. It supports percentage pricing with floors and caps, minimums and parent-child roll-ups. It fits UK and US fintechs collecting through Stripe or GoCardless. It's weaker for continental Europe, where Adyen and Mollie aren't supported. Published price: $799 a month on Growth.

Zuora

Zuora is the enterprise suite. It fits large, listed payments groups with many product lines, a billing operations team and bank-grade procurement on both sides. It's heavy for anyone smaller. No list price, with a median near $170,000 a year in Vendr's data. It supports 40+ payment gateways and has an EU data center in Frankfurt.

Metronome

Metronome meters and rates events in real time at very large scale. It fits fintech infrastructure priced per API call where engineers own billing and payments run on Stripe. It has no native CPQ and collects through Stripe. Published price: 0.8% of billing volume plus $0.04 per 1,000 events. Stripe has owned it since January 2026.

Hyperline

Hyperline is European billing with CPQ and e-invoicing. It fits fintech SaaS selling subscriptions and usage to businesses, with reps quoting from the CRM. It's less suited to transaction-fee pricing at tens of millions of events. Published price: $299 a month plus 0.7% on Launch.

Chargebee

Chargebee is subscription management. It fits fintechs whose revenue is account or platform fees on plans. Percentage-of-transaction pricing isn't its model. Published price: $99 a month plus 0.65% on Flow. It documents EU hosting on AWS in Frankfurt.

Lago

Lago is open-source metering and billing. It fits regulated fintechs that must run billing inside their own infrastructure. Your engineers operate it, and finance features are extras. Price: free self-hosted under AGPL-3.0 (GitHub).

Which platform for which situation

A European processor with fees by region and method, several entities, on Adyen

Pick Solvimon. Nested rules express the rate table without a rule per combination, each entity invoices with its own numbering and tax, and Adyen is supported. Montonio bills percentage-based transaction pricing with invoice minimums across entities this way, and put 10,000+ invoices through in its first month.

A UK fintech with bespoke contracts and a percentage fee with a floor

Pick Sequence. It reads the signed contract into a schedule, handles percentage pricing with floors and caps, and collects through Stripe and GoCardless.

A fintech API with billions of calls, engineering-owned billing, on Stripe

Pick Metronome. Usage is the whole problem, the scale is proven, and it's the same vendor as your payments.

A listed payments group with 30 product lines and a procurement checklist

Pick Zuora. It has the amendment handling, the gateway coverage, the revenue subledger and the partner bench that a group of that size expects.

What we've learned about go-live

Most Solvimon migrations go live within 2 months of contract start, and half inside 6 weeks. Many of them are fintechs doing tens of millions of billable events a month.

Custom pricing doesn't slow a migration down: 2 of the fastest had a bespoke plan per customer. A fintech with 300 merchants and 300 slightly different contracts migrates fast when those contracts are built from the same parts. Test it yourself: take 20 of last month's invoices and try to rebuild each one from the contract and the transaction data alone.

Frequently asked questions

What is the best billing software for fintech companies?

It depends on the price model. For percentage fees with nested rates across European entities, Solvimon. For UK and US contract billing with floors and caps, Sequence. For API-call metering at scale on Stripe, Metronome. For large payments groups, Zuora.

Which billing systems handle percentage-based pricing?

Solvimon and Sequence both support a percentage of transaction value with floors and caps. Solvimon adds nested rules by transaction property. Zuora can model it with configuration.

Why do payments companies outgrow subscription billing tools?

Subscription tools multiply a quantity by a price. Payments pricing is a percentage of an amount, per transaction, with a floor, a cap and a rate that varies by region and method. Teams end up computing fees outside the billing system.

How do fintechs bill from several legal entities?

Each entity needs its own tax registrations, invoice numbering and currency, and e-invoicing rules apply per entity. The multi-entity billing glossary entry explains the setup.

Can a billing system rate tens of millions of transactions a month?

Yes, if it rates per event. Check by sending a real day of transactions in the trial and comparing fees on small and large payments. The usage metering glossary entry covers what to look for.

Where do quotes fit for a payments company?

Merchant agreements are quotes with rate tables. A platform with quoting turns the signed agreement into the billing configuration. The companion guide covers that: billing for sales-led and enterprise deals.

Solvimon makes one of the products on this list. Its founders built Adyen's in-house billing, which handled €1T+ in volume.