Nobody in the chain is paid late because of a missed date.
On a subcontract package every firm, from the main contractor down to the gang on Level 5, is owed money on a fixed clock. SubContractOS counts that clock, collects the evidence behind each valuation, and makes sure the right person signs before any notice goes out.
One valuation, counted day by day
Interim valuation on Sun, 20 December 2026. JCT 2016 subcontract terms, calculated live by the same code the app uses.
| Mon, 4 January 2027 | Payment due | 12 days after the valuation, skipping bank holidays |
|---|---|---|
| Sat, 9 January 2027 | Payment notice served by | 5 days after the due date. Serving late can leave the full application payable. |
| Wed, 13 January 2027 | Pay less notice served by | 5 days before the final date. Only a commercial manager can sign it. |
| Mon, 18 January 2027 | Final date for payment | 14 days after the due date. Money must be in the account. |
The contract's own figures always win. These are the standard JCT 2016 subcontract numbers, used when a subcontract does not state them.
Evidence first, then money
Each obligation in the subcontract becomes a checklist item with its own proof: a photo with a location, an air-test certificate, a signed handover. Firms send it from the phone they already use, and it is filed against the right item.
A valuation cannot go to a notice until every obligation in it has its evidence. A person can override that, and the override is recorded with their name and a reason.
Fourteen firms on one package, three tiers, one picture
- BuildCo UK Ltd · tier 1
- Northgate Mechanical · tier 2
- Brightwire Electrical · tier 2
- EastEnd Electrical · tier 3 (Dave Patel)
- Citadel Fire & Security · tier 2
- …and the rest of the 14 firms on PKG-0412, out of 261 across the portfolio
Demo data: package PKG-0412 in Tower Hamlets, managed by Sarah Okafor. Firms reply on WhatsApp, typically within 11 minutes.
Software does the chasing. People sign.
Four assistants do the legwork. Every decision with legal or financial weight is reserved for a named person, and the database itself refuses anything else, so a bug in an assistant cannot serve a notice.
The assistants
| Hermes | Reads the subcontract and drafts the obligations |
|---|---|
| Openclaw | Chases firms on WhatsApp and files what comes back |
| Ledger | Assembles each valuation and drafts the notices |
| Sentinel | Watches insurance, right-to-work and debarment dates |
What needs a signature
| Decision | Who can sign | Limit |
|---|---|---|
| obligation.publish | qs, commercial manager | none |
| valuation.override_evidence_gate | qs, commercial manager | QS up to £25,000 |
| notice.serve_payment | qs, commercial manager | none |
| notice.serve_pay_less | commercial manager | none |
| entity.suspend_debarment | commercial manager | none |
| cdp.publish | commercial manager | none |
| variation.approve | qs, commercial manager | QS up to £10,000 |
| thresholds.edit | commercial manager | none |
SubContractOS is in development. This site runs on demo data only and sends no real messages. Dates are calculated from the statutory and JCT rules and are not legal advice; check the contract itself before relying on a deadline.