Commercial work does not move in one clean line.
A project may start with demolition, move into rough-in, pause for inspection, continue through installation, and finish with testing, closeout, and warranty obligations. Your revenue should follow that same structure.
But many trade businesses still manage the commercial side with a combination of spreadsheets, accounting software, email threads, and manually updated project notes.
That system can work for one project. Across several active jobs, it becomes a cash-flow risk.
The better approach is to use multi-phase project software for trades that connects completed work, supporting documentation, Progress Billings, and Retentions in one centralised record.
The Excel trap: why spreadsheets break down
Excel is flexible. That is also the problem.
A spreadsheet can be adapted to almost any process, but it does not enforce one process. As a result, every project manager, estimator, and accounts team member may track the same information differently.
The most common problems are predictable:
- Multiple versions of the same project file
- Draws updated in one workbook but not another
- Retentions recorded in notes instead of against the invoice
- Manual formulas overwritten or copied incorrectly
- Supporting photos and sign-offs stored in separate folders
- No clear owner for following up outstanding amounts
- Project managers and finance teams working from different numbers
The issue is not that your team is careless. The issue is that the process depends on memory and manual maintenance.
When a commercial project has 15 phases, several variations, and monthly billing cycles, small errors compound quickly. One missed draw can delay cash collection. One incorrect retention calculation can leave earned money sitting unclaimed. One outdated spreadsheet can create confusion during a client dispute.
The goal is not to eliminate spreadsheets overnight. It is to remove them from the centre of the process.
Progress Billings are more than sending partial invoices
Progress Billings are invoices raised against completed work, agreed milestones, or a defined percentage of the contract value.
Instead of waiting until the entire project is finished, you bill as value is delivered.
For example, a commercial plumbing project might be divided into:
- Mobilization and site preparation
- Underground services
- Rough plumbing
- Fixture installation
- Testing and commissioning
- Final closeout
Each phase has a commercial value. When a phase is completed and approved, the corresponding draw can be billed.
That is different from simply splitting one large invoice into arbitrary installments. A properly structured Progress Billing should answer three questions:
- What work has been completed?
- What amount is billable at this stage?
- What documentation supports the draw?
A clear billing structure improves cash flow because invoices reflect the work already performed. It also gives the customer, general contractor, and internal team a shared view of what has been earned and what remains.
For more complex projects, the billing schedule may use a schedule of values, milestone percentages, or a combination of both. The exact method depends on the contract, but the principle stays the same: bill against verified progress, not guesswork.
Retainage: the cash you earned but cannot collect yet
Retainage, are amounts withheld from a Progress Billing until specific project conditions are met.
A contract might withhold 5% or 10% from each draw. The money is not necessarily disputed. It is held as security until substantial completion, final completion, the end of a warranty period, or another agreed release event.
A simple example:
- Gross Progress Billing: $50,000
- Retainage withheld at 10%: $5,000
- Net amount paid: $45,000
If the project has 10 billing cycles, the total held amount could become significant. Without a dedicated process, that balance can disappear into general accounts receivable.
The risk is especially high when:
- Retainage has different release dates across projects
- The rate changes after a project reaches a certain completion point
- A portion is released at substantial completion
- The balance is dependent on closeout documents
- The warranty period ends months after field work is complete
- Responsibility for follow-up is unclear
Retainage is not just an accounting detail. It is cash that belongs in your forward cash-flow plan.
Contract terms vary by project and jurisdiction, so your team should always confirm the applicable release conditions, notice requirements, and payment rules in the contract. A practical overview of the concept is available in Foreman’s guide to retainage in construction.
Milestone mapping: make billing match the work
The first operational step is to map the project before the first draw is submitted.
Start with the contract value, then break the job into logical phases. Each phase should have:
- A clear description of the work
- An assigned commercial value
- A responsible crew or team
- A completion status
- Required documentation
- A billing trigger
- Any associated retainage rules
The phases should be specific enough to verify, but not so detailed that the team spends more time updating the system than doing the work.
For example, “Mechanical installation” may be too broad. “Level 2 HVAC rough-in complete and inspected” is easier to verify and connect to a billing event.
This structure creates a direct link between operations and finance:
Field completion → approval → Progress Billing → retainage tracking → payment follow-up
It also makes variations easier to manage. Approved changes can be added to the relevant phase instead of being buried in email correspondence or a separate workbook.
Software designed for project jobs with structured phases can keep the parent project visible while allowing each stage to be planned, assigned, and tracked independently.
The audit trail: prove the draw before you submit it
A Progress Billing is easier to approve when the supporting evidence is already organised.
The audit trail should show what was completed, when it was completed, who approved it, and which documents support the amount being billed.
That may include:
- Customer or superintendent sign-offs
- Inspection records
- Job Hazard Analysis (JHA) forms
- Completion checklists
- Progress photos
- Delivery records
- Approved variations
- Test results
- Defect and punch-list updates
- Emails or certificates confirming milestone acceptance
The important point is not simply storing these documents. It is linking them to the right project phase and billing event.
If a customer questions a draw, your team should not have to search through individual inboxes, shared drives, and technicians’ photo libraries. The evidence should be available from the project record.
Digital field documentation makes this process more reliable. Technicians can complete forms, capture photos, and record sign-offs while work is happening. Office teams can then review the information before submitting the next draw.
This creates a practical single source of truth: the field record supports the commercial record.
Live visibility: know what is billed, held, and outstanding
A spreadsheet usually tells you what someone last entered.
A connected system should tell you what is happening now.
At the project level, your team should be able to see:
- Total contract value
- Approved variations
- Completed phase value
- Amount billed this period
- Cumulative Progress Billings
- Amount approved
- Amount paid
- Retainage withheld
- Retainage released
- Balance still outstanding
- Upcoming release conditions
- Documents still required for approval
At the portfolio level, leadership needs a wider view.
Which projects have completed work that has not yet been billed? How much cash is currently held in Retentions? Which customers have outstanding approvals? Which projects are approaching a retainage release date? Where are billing delays affecting working capital?
These answers should not require a manual reporting exercise at the end of each month. They should be available as part of daily project management.
Ascora’s reporting tools provide visibility into job status, work in progress, and financial performance. That visibility helps project and finance teams work from the same numbers instead of reconciling separate systems.
What a trade-specific system should handle natively
The difference between general invoicing software and multi-phase project software for trades is the depth of the workflow.
A suitable system should allow you to manage:
- Structured project phases
- Contract values and approved variations
- Progress Billing schedules
- Partial billing against completed work
- Retentions by project and billing event
- Release dates and conditions
- Attachments, photos, JHA forms, and sign-offs
- Invoice approval and payment status
- Job costs alongside billed revenue
- Portfolio-level reporting
These functions should be connected, not bolted together.
Ascora supports Progress Billings against contract value, Retentions tracked across the life of a project, and invoicing connected to job information.
That means your team can manage the commercial workflow from the same record used to schedule work, collect field documentation, track costs, and monitor project status.
It is a more controlled process than exporting data into Excel, updating formulas, and hoping the latest version reaches the right person.
The control check
Before your next billing cycle, ask:
- 1 source of truth: Can everyone see the same contract, phase, and billing data?
- 3 core figures: Do you know what was billed, what was paid, and what is held in Retentions?
- 100% traceability: Can every draw be supported by a phase status, approval, and field record?
- ↑ cash-flow visibility: Can you see upcoming billings and retainage releases across the portfolio?
If the answer to any of these is no, the process is vulnerable to missed revenue and delayed collection.
You do not need a more complicated spreadsheet. You need a system that reflects how commercial trade work actually happens.
See how Ascora handles multi-phase projects, Progress Billings, and Retentions in one connected platform. Book a demo and move from scattered workbooks to a controlled process in weeks, not months.
Disclaimer: Image for illustrative purposes only. Actual software interface may vary.