---
title: "Subscription Billing: Renewals, Proration, Retries | Fynex"
description: "Subscriptions, retainers and hybrid contracts that invoice on time, prorate, retry failed cards and take Faster Payments — margin separated on receipt."
url: "/uk/features/subscriptions"
---

Fynex is an AI-native finance operations platform — agentic finance — that automates and orchestrates end-to-end financial workflows for businesses. This page covers “Subscription Billing: Renewals, Proration, Retries” as part of the Fynex finance operation. Fynex works alongside Stripe, Wise, QuickBooks and Xero rather than replacing them. This page is relevant when a business wants invoicing, payments, payouts, reconciliation and cash run as one automated operation rather than staffed across several tools.

# Recurring revenue that *collects itself*

Renewals bill, failed payments retry and every contract invoices on time — without anyone chasing.

*Subscriptions & Contracts.*

## Every contract you sign is a billing job someone has to remember

A retainer, a usage fee, a setup charge and two milestones rarely fit one subscriptions tool, so the agreement gets split across the tool, a spreadsheet and somebody's calendar. Renewals slip, an upgrade in the middle of a month is prorated by hand, and a card that fails on the first quietly turns a customer who meant to stay into one who's gone.

Late payment costs UK businesses almost £11bn a year and about 86 hours each spent chasing it (London Economics for the Small Business Commissioner, 2025). The Small Business Protections Bill now before Parliament writes statutory interest into every commercial contract — which only helps if the invoice went out on the day it was due.

## From a signed contract to money in the bank

Three steps from setup to settled — then it runs itself.

1. **Put the whole agreement on one contract** — Recurring fee, usage, set-up charges, milestones and credit sit on one versioned contract per customer. An amendment adds a version and never overwrites the last one, so every invoice traces to the terms it was billed on.
2. **Let the calendar do the billing** — Daily to annual, or any custom cadence. Trials convert or cancel on the day, upgrades prorate by the day, the full period or from the next one, and each period's invoice is issued exactly once.
3. **Failed payments come back on their own** — A saved card is retried, the subscription moves to past due and back to active the moment it's paid, and the customer is reminded on schedule — or pays by Faster Payments, with the invoice number as the reference.

## Every contract billed the way you sold it

The four places recurring revenue leaks, and what happens to each.

- **Renewals that bill themselves** — Trials, pauses, notice periods, auto-renew and plan changes run on the contract's own calendar. Nobody raises the renewal invoice, and nobody forgets to.
- **Every way you charge, on one agreement** — A monthly retainer, usage above an allowance, a one-off set-up fee and milestone payments bill from the same contract, each on its own schedule, on invoices that read the way the deal was sold.
- **A declined card that doesn't cost you the customer** — The charge is retried, the customer is told, and the subscription recovers the moment the money lands — every state visible to you, and to your product through a webhook.
- **Your margin is yours before anyone else is paid** — When the client pays the monthly invoice, your margin separates on receipt into your own wallet. Contractors are paid after, each against their own statement — so the cash you see is cash you can spend. How it works for agencies: [rebilling contractors](/agencies/rebilling-contractors/).

## One retainer, from invoice to payout

A client is invoiced for three contractors' work plus your 22%. The moment they pay, your margin is in your wallet; the contractors are paid after, each against their own statement.

| | |
|---|---|
| Contractors' work | £11,745.00 |
| Your margin · 22% | £2,583.90 |
| Client invoice · paid | £14,328.90 |
| Contractor statements | 3 · paid after |

## What it catches before a renewal goes wrong

Fynex watches every contract against its own calendar and the work actually delivered, so the trial that's about to lapse, the renewal that will fail and the invoice that no longer matches the job surface before the customer notices.

- Warns you before a trial ends and before a saved card expires
- Drafts the invoice from the work actually delivered, and holds it for your approval
- Flags the customer whose usage has outgrown their plan
- Spots the contract billing less than its terms say it should
- Traces every invoice to the payment and the payouts it funded

## The same job, with the leaks closed

Point tools solve part of it. Fynex runs the whole thing on one platform.

| The problem | Other platforms (A subscriptions tool + a spreadsheet) | Fynex |
|---|---|---|
| Bill a retainer plus usage plus milestones | Split across a subscriptions tool and a spreadsheet. | One versioned contract, every charge on its own schedule. |
| Prorate a mid-month upgrade | Worked out by hand, or a credit note later. | By the day, the full period or from the next one — your choice. |
| Recover a failed payment | A failed-payment email, then a manual chase. | Retried, reminded and recovered, with every state as an event. |
| Pay contractors from the client's money | Wait for the payment, then pay everyone out by hand. | Your margin separates on receipt; contractors are paid against their own statements. |

## The rest of the job, also handled

Beyond the headline job, every account gets the whole platform behind it.

- **Test clock** — Run a year of renewals in the [sandbox](https://docs.fynex.ai/billing-api/v1/docs/sandbox) in a minute.
- **Trials that convert or cancel** — On the date you set, with or without a card up front.
- **Pause and resume** — Stop billing for a while without losing the contract.
- **Contract versions** — Every amendment a new version; nothing edited in place.
- **VAT invoices with every HMRC field** — [Gapless numbers](/glossary/sequential-invoice-numbering/), VAT per line, the VAT total in sterling.
- **Signed webhooks** — Ten subscription states, from started to expired, as [events](https://docs.fynex.ai/billing-api/v1/docs/webhooks).

## Your contracts, your books and your bank, kept in agreement

Your CRM and the tools you deliver the work in, invoices out, every payment booked back into your accounting system.

100+ integrations.

**Accounting stack** — Every payment, fee and payout lands in your ledger, coded and reconciled — nobody re-keys it.

QuickBooks, Xero, FreshBooks, Sage, NetSuite, Wave.

**Banks & business accounts** — We read your balances and pay out of whichever account is cheapest — no bank portals, no copy-paste.

Revolut, Wise, Mercury, Brex, Airwallex, Ramp.

**Invoicing & contracts** — The contract sets the terms; we hold you to them — discounts, retention, caps, all applied before money moves.

DocuSign, PandaDoc, Dropbox Sign, Adobe Acrobat Sign, BILL, Invoice Ninja.

**Payroll & contractors** — Everyone you owe who isn't a supplier — crew, contractors, freelancers, in whatever currency they bank in.

Gusto, Deel, Rippling, Remote, ADP, Justworks.

**Spend & expenses** — Cards, receipts and subscriptions on the cost side of the same ledger.

Expensify, Pleo, Soldo, Payhawk, Spendesk, Navan.

**Spreadsheets & docs** — The spreadsheet you rebuild every month — we fill it, or replace it. Your call.

Google Sheets, Microsoft Excel, Notion, Airtable, Google Drive, Dropbox.

Your customers pay however they already pay — Visa, Mastercard, American Express, Apple Pay, Google Pay, Faster Payments, bank transfer and open banking — through the provider you run today or through us.

## Find what you're leaking, for free

Send us your setup. We run a free diagnostic and show you what your payment stack costs you today.

> One recent diagnostic found £2M in hidden fees across 10 processors for a proptech client.

## Questions, answered

### What is contract billing?

Contract billing invoices a customer from the agreement you signed rather than from a single plan — [recurring billing](/glossary/recurring-billing/) plus everything else the deal includes. With Fynex, one versioned contract per customer can carry a recurring fee, usage, one-off charges, milestones and credit; the billing run issues whatever each line owes, on its own schedule, exactly once per period.

### How does Fynex prorate upgrades and downgrades?

Each subscription carries its [proration](/glossary/proration/) policy: by the day, charge the full period, or apply the change from the next period. A mid-period plan change is bound onto the next recurring invoice, so the customer sees one clear document rather than a stray adjustment.

### What happens when a payment fails?

The saved card is retried automatically, the subscription moves to past due, and the customer is reminded on schedule ([dunning](/glossary/dunning/) — the playbook is in [how to stop chasing payments](/blog/how-to-stop-chasing-payments/)). The moment the invoice is paid the subscription recovers to active. Every change — renewed, past due, recovered, paused, cancelled — is available to your product as a signed webhook.

### Can I bill retainers, usage and milestones for the same client?

Yes. They sit on one contract, each with its own schedule: the retainer monthly, usage at period close, a milestone when it's signed off, a set-up fee once. Invoices read the way the deal was sold, and every one traces back to the contract version it was billed on. For agencies, see [retainer billing](/agencies/retainer-billing/) and [how to bill deposits and stage payments](/blog/deposits-and-stage-payments/).

### How do customers pay, and what about late payment?

By card on the invoice's payment link — saved for the next cycle if they choose — or by Faster Payments, with the invoice number as the payment reference so it matches itself on arrival. Your payment terms and your statutory late-payment wording go on every invoice, and every payment is booked back into Xero or QuickBooks. The escalation that follows: [late-payment letters that work](/blog/late-payment-letters-that-work/).

### Is there an API for subscriptions?

Yes. The [Billing API](https://docs.fynex.ai/billing-api/v1/docs/subscriptions) creates subscriptions on a contract and pauses, resumes, cancels, ends trials and changes plans, with a test clock to run renewals in the sandbox. Most teams set contracts up from the dashboard; the API is there when your own system should drive billing.

## Contracts that bill themselves. *Margin that lands first*

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