Cloisa AI
For cross-border tax practices
The coordinated Canada–US tax file, drafted for your review.
Cloisa's AI agents read the client's slips and statements from both countries. They draft the two personal income tax returns: the T1 for Canada and the 1040 for the US. They also draft the working paper that ties the two together. A licensed tax professional reviews and signs every return. Client identifiers never leave the firm.
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Take on more clients
Cloisa does the heavy work on every file, end to end. Your team checks it and signs. Each file takes far less of your time, so you can say yes to more clients.
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Stop referring clients to another firm
A client asks for the other country's return, and most firms refer them out. The relationship often follows. With Cloisa, the whole file stays in your office.
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Get your evenings back in filing season
The work arrives complete. Slips matched, credits in place, every figure checked and tied to its source. You review it and sign, because a licensed professional must be in charge. That is how it should be.
- No cookies
- No scripts
- No third-party requests
- Toronto, Canada
The problem: one client, two tax systems, two packages, every year
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~861,000
US citizens estimated to live in Canada. A US citizen above the filing threshold files a 1040 wherever they live.1
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US$10,000
Penalty per missed US information form, such as Form 5471 or 8938. The statute of limitations stays open until the form is filed.2
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US$1,745–2,745
Published starting fee per year for a coordinated T1 + 1040 file at cross-border firms.3
A cross-border file is two returns that must agree.
A US citizen living in Canada usually has to file in both countries. A Canadian with US income often does too. None of these filings is hard on its own. The hard part: one client needs many of them at once, prepared by hand, every year. The table below shows what a single client can set off.
General purpose AI could draft much of this. But a tax file is full of names, Social Insurance Numbers, Social Security Numbers and account numbers, and the firm answers for every one of them. Typing client records into a public AI chatbot is exactly what a firm cannot do. And those chatbots were trained on the open internet, not on two tax systems whose rules change every year.
So the work is still done by hand. And every filing season, it eats the team's evenings.
| The client has | Canadian side | US side |
|---|---|---|
| Employment and investment income | T1 with schedules; T4, T5, T3 slips | 1040; wages on line 1a, interest on Schedule B |
| Tax paid in both countries | Foreign tax credit on Form T2209 | Form 1116, computed by income basket; treaty re-sourcing where it applies |
| A TFSA | Tax-free | Taxable; FBAR and Form 8938 reporting; funds held inside it reviewed for PFIC |
| Canadian mutual funds or ETFs outside an RRSP | T3 and T5008 slips | PFIC analysis; Form 8621 for each fund |
| An incorporated practice or company | Corporate filings as usual | Form 5471 as a controlled foreign corporation; GILTI |
| Canadian accounts over US$10,000 in aggregate | — | FBAR (FinCEN Form 114) |
| Foreign property over C$100,000 | Form T1135 | — |
1. FVAP, 2020 Overseas Citizen Population Analysis (2018 estimate). 2. IRC ss. 6038(b), 6038D(d), 6501(c)(8). 3. Published 2026 fee schedules at two cross-border firms. Form obligations depend on the client's facts; the table shows common triggers, not advice.
The solution: Cloisa drafts, your tax professional approves
Four steps. Cloisa runs the first three on its own and lines the file up, complete, for review. You go through it when it suits your day. The file waits for you, not the other way around.
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Read
Cloisa reads the client's documents as you have them: slips, statements and prior returns from both countries. No manual entry.
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Map
Each figure placed on the T1 and the 1040, traced to the page it came from.
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Reconcile
Each treatment checked under both tax codes and the treaty, with the rule it relied on quoted next to the figure.
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Approve
The licensed professional reviews field by field and signs. Never the AI agent.
What your tax professional sees
Everything in one clear list. Each number shows where it goes on the Canadian return and where it goes on the US one, with a confidence score beside it. Hover over any number, or tap it on a phone, and the exact spot on the source document pops up. Let go and you are back where you were. No flipping between pages.
| Source | Canada (T1) | US (1040) | Status |
|---|---|---|---|
| T4 employment income | Line 10100From the client's T4 slip, box 14.T4 · Box 14 Employment income 148,250.00 |
Line 1aPlaced on the draft 1040, line 1a, converted to US dollars at the annual average rate.1040 · Line 1a Wages 109,870 USD |
Ready · 99%Why not 100%? 99% is Cloisa's confidence in this field. The last 1% is yours on purpose: click Approve and it is locked in. Approved by you |
| T5 interest | Line 12100From the client's T5 slip, box 13.T5 · Box 13 Interest 1,872.40 |
Schedule BListed on the draft Schedule B, Part I, in US dollars.Schedule B · Part I 1,388 USD |
Ready · 98%Worth a look: the issuer's name differs by one character from last year's T5. Cloisa flags it for your eye instead of assuming. Approved by you |
| TFSA account | Tax-freeTax-free in Canada. Nothing to report on the T1. | FBAR, Form 8938US rules do not recognize the TFSA wrapper: the account is reported on the FBAR and Form 8938. | Flagged: review funds for PFICTwo funds inside this TFSA look like PFICs. Your options: confirm the classification, ask the client for fund statements, or prepare Form 8621 for each. Your call, one click each. |
| Foreign tax credit | Form T2209Draft T2209, the federal foreign tax credit. | Form 1116Draft Form 1116, passive basket, with the rule quoted beside the figure.Canada–US treaty · Art. XXIV Re-sourcing applied |
Draft · needs reviewWaiting on the TFSA decision above: the credits shift if PFIC income changes. |
A working illustration with a simplified sample file: hover or tap the values, approve a field. Like everything on this site, it runs without a single script.
Built to grow your practice, not to replace it
Cloisa cannot sign a return, and it never will. The judgment stays with the professional. What changes is what your hours go to.
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Serve more clients with the team you have
The hours in a coordinated file go to slip-matching, credit sequencing and PFIC checks. When that work arrives drafted and cited, the same professionals handle more files, without hunting for cross-border staff that is hard to hire.
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Say yes to the work you refer away
A client moves to the US, or a US citizen walks in. For most practices that work is too rare to keep the expertise current, so the client gets referred out. With the mechanics drafted and every treatment cited, you keep the client and the relationship.
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Reach people the current cost excludes
Many cross-border filers go unserved because preparing the coordinated file costs more than they can pay. When drafting takes less of the firm's time, that work becomes worth taking, and a market that was out of reach opens up.
The goal, stated plainly: the practices that use Cloisa should serve more clients, offer a broader service, and earn more. We publish progress as it happens in Notes.
Where we are
We are in discovery with cross-border practitioners now, and we are looking for two or three practices to build this with.
Built with practitioners. The coordinated file lives on judgment calls that only the people who prepare them can grade. We are building the product around that judgment from the first day.
The engine generalizes to other regulated document work. Cross-border tax is where it starts.
We are looking for two or three practices to build this with
What that means, concretely: let us watch how one coordinated file is handled in your practice today. An hour of someone's time. No commitment, no software to install. In return, you decide what gets built first, and your practice gets it first.
hello@cloisa.com We reply personally. Client files never change hands during discovery.