---
title: "Retainage, Pay Apps & Job Costing for Subcontractors | Fynex"
description: "For subcontractors on Procore, Buildertrend or Knowify: every pay app tracked to the cash, retainage chased, subs and suppliers paid against the job, posted to QuickBooks or Sage."
url: "/construction"
---

Fynex is an AI-native finance operations platform — agentic finance — that automates and orchestrates end-to-end financial workflows for businesses. This page covers a specialty subcontractor's job money: pay apps tracked to what the GC paid, retainage receivable and payable, sub-tiers paid with lien waivers, and job cost in the books. Fynex works alongside Procore, Buildertrend, Sage and QuickBooks rather than replacing them. This page is relevant when a subcontractor tracks pay apps, retainage and lien waivers across GCs in spreadsheets and only finds out a job's margin at close-out.

# Know what every job made *while you can still act on it*

Pay apps, retainage, subs and suppliers tied to the job — and posted to QuickBooks or Sage.

*For specialty contractors and subcontractors.*

## You float payroll *while the GC sits on your pay app*

Procore runs the job and the GC pays you through it. Your side is still spread out: cash due from every GC across Procore, Textura, GCPay and email; retainage owed job by job; sub-tiers and suppliers to pay on the same job; and a job cost that lands in QuickBooks after the fact. So the real margin shows up at close-out, and the retainage months after that.

## Each part of the job's money, with its own guide

Start with subcontractor payments — retainage held and lien waivers collected before the money goes.

- **Subcontractor payouts & retainage** — Pay every sub-tier and supplier against the job — retainage held, lien waivers collected before the money goes.
- **When does the GC have to release your retainage?** — The cap, the release deadline and the interest on late retainage, in all 50 states.
- **When does the GC have to pay you?** — The days the GC has once it's paid, and the interest on late pay — every state, statute cited.

## See what a pay app leaves you

The GC holds 10% retainage on a $186,000 pay app and pays $167,400. Here's where that goes.

GC pays $167,400:

| Party | Amount | |
|---|---|---|
| Sub-tiers | $121,400 | paid, waivers in |
| Suppliers | $38,700 | paid against the job |
| Your margin | $7,300 | this pay app |

[Run your own numbers](/split-payment-calculator/)

## From the pay app to the margin

Every pay app, every retainage line and every sub payment, tied to the job it belongs to.

1. **Every pay app tracked to the cash** — Each G702/G703 line matched to what the GC actually paid, net of retainage — short pays flagged the day they land.
2. **Retainage you can see, job by job** — Retainage receivable and payable tracked per job and per GC, with release dates chased, not forgotten.
3. **Subs and suppliers paid against the job** — Sub-tiers and suppliers [paid by ACH](https://docs.fynex.ai/payments-api/v1/docs/payouts), retainage held back and the lien waiver collected before the money goes.
4. **True margin per job, in your books** — Every receipt, payment and cost posted to the job in QuickBooks or Sage, so over/under billing is a number, not a guess.

## Procore runs the job. Fynex runs the money it produces

What still happens in spreadsheets around Procore, Buildertrend or Knowify, and what Fynex does with it.

| The problem | Other platforms (Procore + QuickBooks + a spreadsheet) | Fynex |
|---|---|---|
| Know what every GC owes you | Cash due spread across Procore, Textura, GCPay and email. | Every pay app and payment in one list, by GC and job. |
| Track retainage | A spreadsheet of what's held and when it's due. | Retainage receivable per job, release dates chased. |
| Pay subs and suppliers | A transfer per party, waivers chased by email. | Paid against the job, waiver collected first. |
| Job cost in your books | Re-keyed into QuickBooks or Sage; WIP built in Excel. | Posted to the job as it happens; WIP and over/under billing live. |
| See true margin per job | Known at close-out, not while you can act. | Margin per job as costs and payments land. |

## Already on Procore, Buildertrend or Knowify? *Keep it*

It runs the job. Fynex runs the money the job produces — across every GC and into your books.

- **Procore** — The GC approves your pay app and pays you through it. Fynex tracks what every GC owes you and the retainage they hold, and posts the job cost the same day.
- **Buildertrend** — Pays your trades and tracks the budget. Fynex matches the bank, the bills and the invoices to the job, so the margin is real rather than mapped.
- **Knowify** — Writes the G702/G703 and tracks retainage by phase. Fynex follows each payment after the pay app goes, net of retainage, and pays your suppliers against the job.
- **QuickBooks or Sage** — Stays your books. Fynex posts every receipt, payment and cost to the job, so WIP and over/under billing come from the ledger, not a spreadsheet.

## The rest of the job, also handled

The rest of the job's money, from the first pay app to the retainage release.

- **Retainage receivable and payable** — Tracked per job and per GC, chased on the date it's due.
- **Lien waivers, conditional and unconditional** — Collected before each sub-tier payment and tied to the payment that clears them.
- **Pay subs and suppliers against the job** — By ACH, matched to the job and the pay app it came from.
- **WIP report and over/under billing** — Live per job, from the same numbers as your books — not rebuilt in Excel at month-end.
- **Change orders priced into the job** — Approved change orders added to the job's budget and the next pay app.
- **Works with Procore, Buildertrend, Knowify, QuickBooks and Sage** — Reads the job, the pay apps and the books from the systems you run, with one API.

## Your bank, your books and the tools you run the work in, kept in agreement

Your bank, your accounting system and the tools you run the work in. Fynex reads them, does the finance work between them, and writes the result back.

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.

**Job management** — The job is where your profit is decided. We read it, then pay the crew against it.

Jobber, ServiceTitan, Housecall Pro, PaintScout, JobNimbus, Workiz.

**Construction & projects** — Pay apps, subs, retention and change orders — read from the system your PMs already live in.

Procore, Buildertrend, Autodesk Construction Cloud, CoConstruct, Knowify, Contractor Foreman.

**Lead sources & marketing** — Where the jobs come from and what each channel costs — so every won job is attributed back to the ad that bought it, and ROAS stops being a spreadsheet.

Angi, Thumbtack, Yelp, Google Ads, Meta Ads, Nextdoor.

**Phone & customer comms** — Calls matched to the lead that triggered them — speed-to-lead becomes a number you can see, not a guess.

Quo (OpenPhone), RingCentral, Dialpad, CallRail, Aircall, Twilio.

Your customers pay however they already pay — Visa, Mastercard, American Express, Apple Pay, Google Pay, ACH, 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.

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

Fynex is Merchant of Record, so the payment risk on every pay app and sub payment sits with us, not your company.

- **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.

## Questions, answered

### What does Fynex do for a specialty contractor?

Fynex runs the money side of every job for a specialty subcontractor — the trade that's paid by a GC and pays sub-tiers and suppliers of its own. It tracks each pay app to what the GC actually paid, chases retainage receivable and payable job by job, pays sub-tiers and suppliers by ACH with the lien waiver collected first, and posts every receipt, payment and cost to the job in QuickBooks or Sage. Procore, Buildertrend or Knowify keep running the job.

### How does Fynex track retainage?

Retainage runs both ways for a subcontractor: retainage receivable, held by the GC on each pay app, and retainage payable, held back from your own sub-tiers. Fynex tracks both per job and per party, shows what's held and when each release is due, and chases the GC's release at substantial completion instead of leaving it in a spreadsheet. When retainage is released, the payment is matched to the job it belongs to.

### Can Fynex handle lien waivers?

Yes. Conditional and unconditional lien waivers are collected from each sub-tier and supplier and tied to the payment that clears them — a conditional waiver before the payment goes, an unconditional one once it has cleared. The paperwork matches the money on the same job instead of being chased by email.

### Does Fynex show job costing and margin per project?

Yes. Every pay app, receipt, sub-tier payment and supplier cost posts against the job in QuickBooks or Sage, so true margin per job is a live number as costs land — not something you reconstruct at close-out. You see which jobs and which crews actually make money while you can still act on it.

### Does Fynex work for subcontractors, not just general contractors?

Yes — the subcontractor is who it's built for. A specialty sub is paid by a GC and pays its own sub-tiers and suppliers, so it carries both sides: pay apps and retainage receivable coming in, sub payments, lien waivers and retainage payable going out. Fynex runs both sides on the same job, so the margin is the difference between them, not a guess.

### Does Fynex work with Procore and QuickBooks?

Yes. Procore holds the job, the pay app your GC approves and often the payment; QuickBooks holds your books. Fynex reads both and your bank, matches every payment to its job and pay app, and posts the job cost to QuickBooks the same day — the Procore QuickBooks integration question, answered at the job level rather than the invoice level.

### Does Fynex work with Buildertrend or Knowify?

Yes. Buildertrend pays your trades and tracks the budget; Knowify writes AIA-style pay apps and tracks retainage by phase. Fynex works beside either: it matches the bank, the bills and the invoices to the job, follows each payment after the pay app goes, and keeps QuickBooks agreeing with the job — so the margin is real rather than mapped.

### Can Fynex read our AIA G702/G703 pay applications?

Yes. The G702 summary and the G703 continuation sheet are read line by line against your schedule of values, so each payment the GC makes is matched to the lines it covers, net of retainage. A short pay shows which line was cut, not just that the total came in low.

### Can Fynex build our WIP report and over/under billing?

Yes. Because every pay app, cost and payment is already posted to the job, the work-in-progress report builds itself: percent complete, billed to date, cost to date and the over/under billing on each job, live rather than rebuilt in Excel at month-end. It's the report your surety and your bank ask for.

### How fast can we start, and what does it cost?

You can test the full flow — pay apps, sub-tier payments, retainage and reconciliation — in a sandbox before going live. Pricing is public: 1.4% per payment on a US-issued card plus $0.20 per authorization, payouts at 0.5% each ($1 minimum) plus $100 a month, and larger flows priced on volume, corridors and risk ([pricing](/pricing/)). Start with a free diagnostic of what your current pay-app-to-payment process is costing you.

### Can payments connect to our job costing system?

Yes. Payment runs can be raised from the system that already holds the job — the [Payments API reference](https://docs.fynex.ai/payments-api/v1/docs) documents [payment runs](https://docs.fynex.ai/payments-api/v1/docs/payouts) and [holding each subcontractor's verified bank details](https://docs.fynex.ai/payments-api/v1/docs/payees).

## Run the job. *Know what it made before close-out*

---

The AI finance layer for platforms and operators. It runs the money chain and keeps more of it in your business. One platform instead of a dozen.

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