AI for accounting and tax firms: a practical guide before busy season

Why the pressure keeps rising

Busy season compresses a year of work into a few months. In the US, partnership and S-corporation returns are due on 15 March 2027 and individual returns on 15 April 2027. In Canada, most individual returns and payments are due on 30 April 2027, with self-employed filers having until 15 June to file.

The people to do that work are scarce. In Robert Half's survey, 61% of finance and accounting leaders said skilled professionals are harder to find than a year ago. Meanwhile individual accountants have already embraced AI: Karbon's State of AI in Accounting 2026 found 98% of accounting professionals use it, saving about an hour a day on average. Yet only 21% of firms have a documented AI strategy, and 40% worry about losing clients to firms that use AI better.

The gap is in the firm's workflow, not in anyone's chat window. That's where the hours are.

Five places AI pays off for a firm

1. Client intake and engagement. New clients are onboarded with the right engagement letter, a checklist built for their situation and the questions you always ask, before anyone books a meeting.
2. Document collection without chasing. Each client gets a personal checklist and polite, persistent reminders until everything is in. Your team sees who is complete and who isn't, without sending a single reminder by hand.
3. Reading and sorting documents. Slips, statements, receipts and prior-year returns are read, named, filed and matched to the checklist, with figures pre-filled into workpapers for an accountant to review.
4. Client status questions. "Did you get my documents?" and "When will it be done?" are answered instantly from the file's real progress, so your team stops being interrupted.
5. Review-ready files. Before a file reaches a senior, the system checks it's complete, flags anything unusual against last year and lists the open questions.

What it looks like in practice

A client uploads six documents on a Sunday evening with a note: "Here's what I have so far." Within minutes each document is read and matched to their checklist. Two items are still missing, an investment slip and a donation receipt, so the client gets a friendly message listing exactly those two. The figures from the other four are pre-filled into the workpaper, and the file joins the review queue the moment the last document arrives. Nobody on your team touched it.

Where the time goes today

Document collection is the problem firms name most often. In one survey of 150 US accountants, 69% said they spend too much time gathering documents from clients, and a 2025 survey of 816 firm owners again ranked getting documents from clients as their biggest workflow issue. Every reminder sent by hand, every "is this the right slip?" email and every status call is time a qualified accountant isn't spending on review or advice.

Rules to build around

• Professionals sign, AI prepares. AI collects, reads, sorts and drafts. Accountants review, decide and sign. Build that line into every workflow, with a person approving anything that goes to a tax authority or contains advice.
• Data security is a legal duty. In the US, the IRS reminds tax professionals that they must have a written information security plan to protect client data. Any AI system should fit inside that plan: accounts you control, access limited to what each workflow needs, and business-grade AI services that don't train on your data.
• Tell clients what's automated. Clients like fast answers. Be clear when a message is automated, and make it easy to reach a person.
• Start before the rush. Don't launch something new in March. Build and test in November and December, run it on a small group of clients, then switch everyone on in January.

How to measure it

• Days from engagement to all documents received
• Reminders sent by hand per client (target: zero)
• Hours of data entry per return
• Client status calls and emails per week
• Returns completed per staff member during busy season

Off-the-shelf portal or built for you?

Client portals and practice management tools already handle uploads and basic reminders, and if yours works, keep it. A built system earns its place when it connects the pieces: reading what clients upload, updating your practice management system, answering clients from real file status and preparing workpapers, all around how your firm already works. For typical costs, see our guide to AI implementation costs.

Frequently asked questions