---
title: "Rebilling Contractors & Pass-Through Costs | Fynex"
description: "Rebill contractor work and pass-through costs with your markup, separate your margin on receipt, then pay each contractor on their own statement."
url: "/uk/agencies/rebilling-contractors"
---

Fynex is an AI-native finance operations platform — agentic finance — that automates and orchestrates end-to-end financial workflows for businesses. This page covers “Rebilling Contractors & Pass-Through Costs” 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.

# Rebilling contractors, *with your margin taken first*

Invoice the client for contractor work plus your markup, keep your margin when they pay, then pay each contractor.

*Billing for agencies.*

## Rebilling puts other people's money through your account

Rebilling (or pass-through billing) is invoicing a client for work or costs supplied by someone else — freelancers, subcontractors, media spend, software — usually with a markup. The agency collects the full amount and pays the contractors out of it, so every rebilled invoice is really several: the client's, one per contractor, and your margin in between. Done in a spreadsheet, the margin is the last number anyone sees, and a client who pays late means contractors are paid from your own cash.

In the UK, rebilled contractors carry off-payroll (IR35) status questions and, on construction work, CIS deductions of 20% or 30% on labour — obligations the client invoice doesn't show. Each contractor's payment needs its own document and its own trail back to the client money that funded it.

## How contractor rebilling runs on Fynex

One client invoice in; your margin, then every contractor, out.

1. **Invoice the client with your markup built in** — Contractor work and pass-through costs go on the client's contract with your markup as a percentage or a fixed fee. The client gets one invoice that reads the way you sold the work.
2. **Your margin separates on receipt** — The moment the client pays, your margin moves into your own wallet — visible and spendable while the contractors' share is still waiting to be paid out. Your cut is never the residue of a spreadsheet.
3. **Each contractor paid against their own statement** — Every contractor gets a [statement](/glossary/self-billing/) for their own amount, and is paid from the client's money once it has arrived — never from your cash while the client is still at day 38.
4. **One trail from client invoice to every payout** — Each client invoice traces to the payment that settled it and to every contractor payout it funded, so the record behind each contractor's payment — and your IR35 and CIS paperwork — sits on the same trail.

## 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 (Accounting software + bank transfers) | Fynex |
|---|---|---|
| Invoice the client with a markup | Built line by line from contractor invoices. | Contractor work and markup on the client's contract. |
| Know your margin | Worked out after everyone is paid. | Separated on receipt, in your wallet before payouts. |
| Pay contractors | Bank transfers from your own account, often before the client pays. | Each paid against their own statement, from the client's money. |
| Year-end contractor records | Rebuilt from bank statements. | Invoice-to-payout trail per contractor, exported. |

## Questions, answered

### What is rebilling in an agency?

Rebilling is charging a client for work or costs supplied by third parties — freelancers, subcontractors, media, licences — usually with a markup on top. The agency invoices the client for the total, collects it, and pays the third parties out of it. It is also called pass-through billing or cost rebilling; the contractor side is often [self-billed](/glossary/self-billing/).

### How do agencies mark up contractor costs?

Either as a percentage on top of the contractor's cost (a 20–30% markup is common) or as a fixed management fee. In Fynex the markup is part of the client's contract, so the client invoice shows the total the way you sold it, and your margin is separated automatically when the invoice is paid.

### Should I pay contractors before the client pays me?

Paying contractors before the client pays funds the client's payment terms from your own cash. With Fynex the client's payment arrives first, your margin separates on receipt, and each contractor is paid from the money that funded their work — against their own statement. The same mechanism powers [split payments](/features/split-payments/) and [payouts](/features/payouts/).

### How do IR35 and CIS affect rebilled contractors?

Under the off-payroll rules (IR35), a medium or large client decides a contractor's status and the fee-payer — often the agency — carries the tax liability if the contractor is inside IR35. On construction work, CIS requires deductions of 20% (registered) or 30% (unregistered) from the labour element. Fynex doesn't make those determinations; it gives each contractor payment its own statement and trail back to the client invoice.

### Can I see which client payment funded which contractor payout?

Yes. Every Fynex invoice can be traced to the payments that settled it and the payouts those payments funded, with the amount attributed to each — the settlement trail for any client, contractor or month, documented in the [invoices reference](https://docs.fynex.ai/billing-api/v1/docs/invoices). For the retainer itself, see [retainer billing](/agencies/retainer-billing/).

## The rest of the agency billing layer

Every guide below runs on the same contracts, invoices and payouts. Start with one, or run the whole stack.

- **Retainer billing** — Retainers that invoice, collect and roll over on their own — with overage, set-up fees and milestones on the same contract.
- **Subscriptions & Contracts** — Contracts that bill themselves, with your margin separated first.

## 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.

## Your money, held under a licence, not a promise

We can be your Merchant of Record, with your funds held by a licensed e-money institution. Most tools can't.

- **Your funds, safeguarded** — Customer funds are held by Fondy Ltd, an FCA-authorised e-money institution (FRN 900705).
- **PCI DSS Level 1** — The highest card-data security standard, on by default.
- **Audit logs** — Every movement traceable and ready for review.
- **Built-in KYC / KYB** — The switch that turns the business on.

## Bill the client once. *Your margin first, then everyone else*

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