Mercury vs Relay: Banking for a Commercial Architecture Studio

A project that stalls between design development and construction documents, waiting on a client decision or a permitting delay, can sit for months without generating new billing while the firm's overall cash position looks fine because other projects are still moving. A dedicated sub-account per active project, funded by that project's phase billing, makes a stalled project visible immediately: its balance simply stops growing while everything else keeps moving. Relay's free, instant sub-accounts make this practical even for a small studio running several projects at once; Mercury's account structure supports the same discipline and adds an API for a firm running dedicated project management software that wants to pull balances in automatically.

Set up phase tracking in these steps:

1. Open a dedicated sub-account for each active project, so every project has its own visible balance.
2. Fund each one from that project's phase billing, which makes a stalled project obvious because its balance stops growing.
3. Add a shared reimbursable expense account and a tax reserve account alongside the project accounts.
4. Reconcile the reimbursable account against client reimbursements regularly, so fronted costs never compete with payroll.

Renderings, model-making, specialty consultant fees and travel to job sites are routinely fronted by the firm and billed back to the client, often with net-30 or longer reimbursement terms. Fund a dedicated reimbursable expense account from project retainers specifically so these costs never compete with payroll for available cash, and reconcile it against client reimbursement at each phase billing rather than letting it run as an open tab that's only settled at project close.

Firms that collect a meaningful retainer at project kickoff are holding cash that needs to last through the early design phases before further billing catches up. The effective federal funds rate is at 3.63%¹ right now, and Mercury's automated Treasury sweep captures yield near that level on cash sitting above your working buffer, which fits a retainer cushion well: money that needs to stay liquid but isn't going to be touched for weeks or months at a time. Relay's savings sub-accounts pay a published rate too, without the same automated sweep into Treasury instruments specifically.

A firm carrying a client through a slow payment stretch, common when a client's own financing or ownership situation changes mid-project, sometimes needs a short-term credit line to keep its own team paid. That credit is priced off the bank prime rate, currently 6.75%², so weigh that real cost against simply pausing work on a chronically slow-paying client until their payments catch up, which is sometimes the better answer even though it feels uncomfortable to say to a client directly.

A studio running dedicated project management or practice management software gets more from Mercury's API, connecting bank data to phase billing and reimbursable tracking that already lives in that system. A smaller studio running phases and reimbursables out of a spreadsheet alongside QuickBooks or Xero can often start with Relay, whose accounting integrations and extra checking accounts on the free plan (up to 20 per business per its pricing page) may cover the need without custom integration work, at least until the practice grows enough to justify more specialized software.stify dedicated software.

Count how many active projects you typically run at once, since that's roughly how many project sub-accounts you'll want. Estimate your typical reimbursable expense volume and reimbursement lag so that reserve is sized correctly from the start. And check with whoever handles your books which platform's integration they already know, since that familiarity saves real time across a busy project season compared to learning a new export format from scratch.

A studio that starts with one or two principals handling both design and the books eventually reaches a size where nobody has time to reconcile project accounts by hand anymore. That transition, usually somewhere around a half dozen active projects running at once, is the natural point to either bring in a part-time bookkeeper on Relay's role-based access or invest in project management software connected to Mercury's API. Studios that wait too long past that point tend to discover phase billing has drifted out of sync with actual project cost only when a principal finally sits down to reconcile several months at once, which is a much harder problem to untangle than catching it monthly would have been.

A studio that's mostly done tenant improvement work and takes on its first ground-up commercial build should treat that as a reason to revisit its account structure, not just its design process. A longer timeline, larger reimbursable volume and a bigger retainer cushion all change the math on which platform features actually matter, and a setup that fit years of smaller projects may need real adjustment for a project of a different scale.