A consulting firm books flights to a client site, pays a subcontractor to help deliver a project, and bills both back to the client at cost. It looks like a wash: money goes out, the same amount comes back in. Whether GST/HST applies to that pass-through amount, and whether it counts as revenue on the firm’s own books, depends on how the arrangement is actually structured, not on whether a markup was added.
This is a different question from the mechanics covered in subcontractor expenses for IT consulting firms, which focuses on T4A reporting and registration checks for the subcontractor relationship itself. This guide covers the billing side: how travel, subcontractor cost, hardware, and other client-billed expenses should be treated for GST/HST and revenue reporting once the decision to bill them back has already been made.
Billable Expense vs. True Disbursement
Most amounts a consulting firm bills back to a client are billable expenses, not disbursements, even when they are passed through at cost. A billable expense is a cost the firm incurred to deliver its own service, and rebilling it is part of the firm’s supply to the client. Travel to a client site, a subcontractor brought in to help deliver a project, and software licensed specifically for a client engagement are typically billable expenses under this framing.
A true disbursement requires the firm to be acting as the client’s agent when the cost was incurred, meaning the underlying supplier’s invoice is effectively addressed to the client, with the firm only handling the payment logistics. CRA’s guidance on disbursements treats this as a narrow category, and it needs to be established by how the engagement is actually structured, not assumed because an invoice happens to show a cost passed through without markup.
The distinction matters because it changes the GST/HST calculation, not just the bookkeeping. A billable expense is billed with GST/HST on the full amount, as part of the firm’s own supply. A true disbursement is passed through at the amount the original supplier charged, including whatever GST/HST that supplier charged, without the firm’s own GST/HST layered on top.
GST/HST on Billed-Back Expenses
For the billable-expense category, which covers most consulting pass-through costs, GST/HST applies to the full invoice the firm sends the client, including the reimbursed portion. The firm separately claims an input tax credit on any GST/HST it paid to the original supplier (an airline, a hotel, a subcontractor), the same way it would for any other business expense used to deliver a taxable supply.
Worked example. A firm pays CAD $1,200 for flights and hotel to deliver a project on-site, and CAD $4,000 to a subcontractor who assisted with the delivery, both including GST/HST paid by the firm. The firm bills the client CAD $5,200 for these costs plus its own project fee, and charges GST/HST on the combined invoice total, not just the fee portion. The firm claims input tax credits on the GST/HST it paid to the airline, hotel, and subcontractor.
Treating the CAD $5,200 as a disbursement and billing it without GST/HST, on the reasoning that it was passed through at cost, understates the GST/HST the firm should be charging and can surface as an assessment if the file is reviewed. The at-cost framing addresses margin, not GST/HST treatment.
Recording Reimbursed Costs on the Books
The bookkeeping question is separate from the GST/HST question, but the two are often confused in the same way. Some firms net client-reimbursed costs against the original expense, so the expense line shows only the firm’s own unreimbursed cost and the reimbursement never appears as revenue. This understates both the expense and the revenue side of the books.
The gross approach, recording the original cost as an expense when paid and the client reimbursement as revenue when billed, keeps both sides visible and is generally the cleaner method for a growing consulting firm. It also matters for anything measured against revenue: a firm netting CAD $80,000 a year in pass-through subcontractor and travel costs against expenses, instead of recording it as revenue, is understating its own top line by that amount, which can distort the kind of margin analysis covered in project profitability for small consulting firms and misstate where the firm sits against revenue-based thresholds like the small business deduction or GST/HST filing frequency.
Where the Contract Terms Matter
Whether a cost is billed as a disbursement or a billable expense should be decided at the engagement-terms stage, not worked out after the fact from how an invoice happens to be formatted. A contract that explicitly names the firm as the client’s agent for certain categories of cost (client-approved travel booked directly through the client’s own systems, for example) supports disbursement treatment for those specific items. A contract that is silent on this, with the firm simply incurring costs and billing them back as part of project delivery, defaults to billable-expense treatment for GST/HST purposes.
Firms that want disbursement treatment for a category of cost, rather than defaulting into billable-expense treatment by not addressing it, need that structure reflected in the engagement letter or master services agreement, not introduced retroactively when a specific invoice is being prepared.
Related Articles
- Subcontractor Expenses for IT Consulting Firms covers T4A reporting and GST/HST registration checks for the subcontractor relationship itself, separate from the billing question covered here.
- Project Profitability in a Small IT Consulting Firm covers how pass-through cost tracking feeds into project-level margin analysis.
- The First $1M Consulting Firm: What Changes covers how revenue reporting accuracy, including gross versus netted pass-through costs, becomes more consequential as a firm scales.
- Deposits, Retainers, and Deferred Revenue for Consulting Firms covers a related but distinct billing question: advance client payments held before work is delivered.