Percentage-of-Completion Accounting for Engineering Firms

Under percentage-of-completion accounting, revenue is recognized as work progresses against the total estimated project scope, typically measured by cost incurred relative to total estimated cost. That means your system needs an accurate, current estimate of total project cost at all times, not just at the start, since a scope change or an unexpected site condition changes both the numerator and denominator of that calculation. Sage Intacct's project accounting handles this pattern natively and tends to be the faster path to accurate percentage-of-completion reporting for a single-entity firm.

NetSuite covers the same ground with additional operational depth, which becomes relevant once a firm is also managing significant subcontractor procurement or multi-entity licensing across state lines.

Engineering firms often need a defensible overhead rate, direct project cost plus an allocated share of firm overhead, both for client billing on cost-plus contracts and for government work that requires a specific overhead rate methodology. That rate needs to be calculated consistently and updated regularly, not set once and forgotten, since a stale overhead rate either underbills clients or makes projects look less profitable than they actually are. Both platforms can track this with the right project and dimensional structure, but the calculation itself needs a deliberate, documented methodology someone owns.

A firm bidding public infrastructure work often needs that overhead rate to survive an outside audit, which means every allocation assumption behind it has to be documented and defensible, not just internally consistent. That documentation burden is a process discipline question first and an ERP configuration question second, though the right system makes it far easier to produce the supporting detail an auditor asks for.

Gross margin also reads differently across engineering disciplines and project types, so benchmark your own numbers by project type rather than leaning on one blended industry figure¹.

For a single-entity firm operating out of one or two offices, Sage Intacct's project accounting and dimensional reporting typically cover percentage-of-completion tracking, overhead allocation, and project-level margin without the heavier implementation NetSuite requires. NetSuite becomes the stronger fit once a firm is licensed and operating as separate legal entities across multiple states, which is common for firms doing public infrastructure work that requires local licensure structured as its own entity.

A small engineering practice with a handful of concurrent projects and simple time-and-materials billing can run adequately on QuickBooks paired with a construction- or project-costing add-on. The clear signal you've outgrown it is when calculating percentage-of-completion revenue for your active projects takes a multi-day manual exercise each month instead of a report you can pull in minutes. That's usually also the point where payables days on subcontractor and material costs start to matter enough to need dimensional tracking rather than a flat expense category².

Have each vendor demonstrate percentage-of-completion revenue recognition on a real project with a mid-project scope change, since that's the scenario that actually tests whether the system handles a moving cost estimate correctly. Ask how overhead rate allocation flows into project margin reporting, and confirm whether the methodology matches what a government cost-plus contract would require if that's part of your client base. Get a straight answer on implementation timeline for a firm your size, since a firm mid-project when a migration starts is taking on real risk.

Ask each vendor to show you the following:

• Percentage-of-completion revenue recognition on a real project that has a mid-project scope change and a moving cost estimate.
• How overhead rate allocation flows into project margin reporting for your firm's own cost structure.
• Whether the overhead methodology matches what a government cost-plus contract requires, if you do that work.
• How quickly an updated total cost estimate changes the percentage complete and revenue recognized to date.

Engineering firms rarely have a truly quiet stretch, but some periods carry fewer active project transitions than others. Pick a migration window deliberately, ideally avoiding a stretch when several major projects are simultaneously approaching milestone billing, and run a full parallel percentage-of-completion calculation on both systems for at least one billing cycle before cutting over. That parallel run is the cheapest insurance you'll buy against a revenue recognition error that would otherwise surface for the first time in front of a client or an auditor.

Bring your project managers into that parallel run, not just the accounting team, since they're the ones with the clearest read on whether a project's percentage complete actually matches reality on the ground. A cost-based completion percentage can drift from physical progress on a project with front-loaded material purchases, and a project manager will usually spot that mismatch faster than a number on a report will.