// Subcontractor payments, done right

Stop chasing retention spreadsheets.
Pay subcontractors right - every time.

Retention and Deductions take two of the messiest parts of subcontractor payment - withholding retention until practical completion, and applying CIS, material costs and equipment charges - and turn them into rules that run themselves. Subcontractors see exactly what they're owed and what's being held. You see the audit trail. Nobody sees a spreadsheet.

5%
Typical retention
1-click
Milestone release
CIS
Correct order, every time
0
Reconciliation calls
DuoApp does the bit your finance team hates - retention, CIS, materials, plant hire - automatically, transparently, and right first time.
Retention

Held automatically. Released in one click.

Every time a subcontractor submits an invoice, DuoApp automatically holds back the percentage you've agreed in advance and parks it in a running balance. When you hit a milestone, you release the right amount with one click.

  • Set the rules once. Pick a percentage and a cap per subcontractor. After that, retention happens automatically.
  • Cap protection built in. Once a subcontractor's retention hits the agreed maximum, DuoApp stops withholding.
  • One-click release at milestones. Practical completion, end-of-defects, or a custom date - seconds, not an afternoon.
  • Subbies see it live. A "My Retention" page shows exactly what's held, what's been released, and when.
  • Defensible audit trail. Every withholding and release logged with date, amount, and notes. Disputes evaporate.
Jenkins Plastering · My Retention5% · £10k cap
£7,240
Currently held
£3,500
Released to date
£10,000
Cap
12 MayINV-2026-01425% of £4,800Held£240
05 MayINV-2026-01385% of £6,200Held£310
28 AprPractical completion - Maple Court Phase 1Released by K. BriggsReleased+£3,500
Before

"How much retention are we holding for Jenkins Plastering?" → 20 minutes of spreadsheet hunting, still not sure.

After

Open their record. The number's right there, with every transaction that built it up.

Deductions

CIS, materials, plant hire - itemised, every time.

Deductions handles every cost you legitimately take off a subcontractor's invoice by setting up reusable rules. Fixed amount or percentage. The maths runs in the right order, every time, with full transparency.

  • Set it once, apply forever. "CIS 20%", "Materials £150/week", "Plant hire 8%" - defined against the subby and applied automatically.
  • Fixed amounts or percentages. Flat fee or proportional - DuoApp handles both and labels each clearly.
  • CIS-correct order of operations. Retention comes off first, then deductions are calculated on what's left - exactly as HMRC and your contracts require.
  • No nasty surprises. Subcontractors see a clean breakdown on every invoice: gross, retention, each deduction itemised, net.
  • Smart edge-case handling. If an invoice is too small to absorb a fixed deduction, DuoApp part-applies what it can and tells you.
INV-2026-0142 · Jenkins Plastering12 MAY 2026
Gross invoiced£4,800.00
Retention5% of gross−£240.00
After retention£4,560.00
CIS20% on labour−£820.80
Materials suppliedPlasterboard & skim - wk 19−£150.00
Plant hireTower scaffold - 8%−£364.80
Net to pay£3,224.40
Before

"Did we deduct the £400 of materials we gave Tom last month?" → Three people check, two disagree, one finds it.

After

It came off the invoice automatically the moment Tom submitted it. Nobody had to remember.

// One workflow, five steps

How they work
together.

Together, Retention and Deductions turn the most error-prone moment in any construction payment - calculating what a subcontractor is actually owed - into a workflow that runs itself.

Worked example · £10,000 invoice from Jenkins Plastering

5% retention · 20% CIS · £150 materials this week.

01

Invoice submitted

Subcontractor submits for completed work.

£10,000.00
02

Retention withheld

5% (£500) parked in their retention balance.

−£500.00
03

Deductions applied

CIS 20% on labour, plus £150 of materials supplied.

−£2,050.00
04

Subby paid

Clean, itemised invoice showing exactly how the figure was reached.

£7,450.00
05

Retention released

At practical completion: one click. Subby paid the held amount with full record.

+£500.00
// Who it's for

Designed for the people who do this every week.

Contract managers & finance

Currently tracking retention in Excel and dreading reconciliation. DuoApp does the maths, keeps the audit trail, and makes the answer one click away.

Subcontractors

Want to know - at any moment - what's being held and what's been deducted. They get a clean, itemised page they can check themselves. Calls about "why is my payment short?" stop.

Project managers

Release retention at milestones without spreadsheet reconciliation. The numbers add up before they touch the screen.

No more reconciliation calls. No more disputes.

See Retention & Deductions running on your own subby setup - bring a real contract, we'll wire up the rules in 30 minutes.

Book a demo →Sign up free