AI agents for business finance: what they can and can't do
What AI agents can do in bookkeeping, close, collections and compliance today, where a person must stay in charge, and how to judge a product.
The short answer
GST/HST-registered businesses in Canada can claim input tax credits (ITCs) for tax paid on purchases used in their commercial activities, but each claim needs supporting documents whose required details rise with the purchase amount, at under $100, $100 to $499.99 and $500 or more. Most businesses have four years from the return's due date to claim, and the CRA generally requires records to be kept for six years. An AI finance agent can check every supplier document against these tiers before a return is drafted; eligibility questions stay with you or your accountant.
Why ITC records matter
For a GST/HST registrant, input tax credits reduce what you remit. They are also one of the first things reviewed if the CRA asks questions. A claim without the right supporting document can be denied, even if the purchase was real and the tax was paid. The fix is usually simple: collect the right details at the time of purchase.
What the document must show
The information required depends on the total amount paid or payable, including GST/HST. As summarised from CRA requirements:
| Purchase total | Information needed |
|---|---|
| Under $100 | Supplier's legal or trading name, the invoice or payment date, and the total amount paid or payable |
| $100 to $499.99 | All of the above, plus the supplier's GST/HST registration number and the GST/HST charged, shown separately or with a statement that the total includes it |
| $500 or more | All of the above, plus your name or business name, the payment terms and a description of each good or service sufficient to identify it |
Check the CRA's current list before relying on this summary; details such as how rates and amounts must be shown are set out in its guidance.
Time limits and retention
- Most businesses have four years from the due date of the return for the period in which the ITC could first have been claimed. Some larger businesses and financial institutions have shorter periods.
- Books and records, including documents supporting ITCs, generally have to be kept for six years from the end of the year they relate to, and the CRA can ask for them at any point in that time.
- Electronic records are acceptable if they meet the CRA's requirements, so a clear image linked to the transaction is usually enough.
What a finance agent can check
- Read each supplier invoice or receipt as it arrives and record its total, including GST/HST.
- Apply the right tier and check that every required detail is present, especially the supplier's registration number from $100 upwards.
- Hold back any claim with missing details and ask the supplier or staff member for a corrected invoice while the purchase is recent.
- Flag purchases in categories where credits may be restricted, such as meals and entertainment or items with personal use, for a person to decide.
- Track claims not yet made, so none passes its four-year limit unnoticed.
- Keep the document linked to the claim for the full retention period.
What stays with a person
- Whether a purchase is used in commercial activities, and in what proportion if use is mixed.
- Treatment of restricted categories and of capital property.
- Whether a supplier's registration number is valid if there is doubt. The CRA provides a registry to check numbers, and a person should decide what to do when one does not match.
A worked example
Example figures only. A Halifax café, registered for HST, makes about 120 purchases a month. In one quarter its bookkeeper finds that claims worth $1,140 in HST are missing details.
- The café adds an AI finance agent. It checks each document as it arrives.
- A $380 equipment repair invoice has no HST registration number. The agent holds the $49 claim and emails the supplier for a corrected invoice, which arrives in four days.
- A $640 catering supply invoice is addressed to the owner personally, not the café. The agent flags it; the owner confirms it is a business purchase and asks the supplier to reissue it.
- A $72 restaurant bill is tagged as entertainment and sent to the bookkeeper to decide the allowable portion.
- By quarter end, held-back claims have fallen to $95, all with requests outstanding. The agent drafts the return; the bookkeeper reviews and files.
Common reasons claims fail
- The supplier's GST/HST number is missing from an invoice of $100 or more.
- An invoice of $500 or more is addressed to the owner personally or to no one.
- The purchase was partly personal and the business share was not worked out.
- The receipt is a card slip showing only the total, with no supplier details.
- The claim was made after the time limit, because the invoice sat in a drawer.
- Tax was claimed on a supplier that was not registered and did not charge GST/HST.
Each of these is visible at the moment the document arrives, which is why checking on arrival, not at quarter end, saves most of the lost credits.
Good habits
- Capture at purchase
- Photograph or forward the receipt the same day.
- Ask suppliers once
- Request that all invoices show your business name and their registration number.
- Separate personal spending
- Use business accounts and cards only for business.
- Review restricted items monthly
- Do not leave judgement calls until the return is due.
Where Pryme fits
The Pryme Finance agent records every action with its source document, so each ITC claim carries the invoice that supports it, and it tests controls continuously. For Canadian businesses with few taxable costs, the GST/HST Quick Method may be an alternative. Read Can AI do your bookkeeping? for the general limits. See also AI finance agent vs an expense management app.
Questions people ask
What do I need on a receipt to claim an ITC?
It depends on the total. Under $100 you need the supplier name, date and amount; from $100 you also need the supplier's GST/HST number; from $500 you also need your business name, payment terms and a description. Check the CRA's current requirements.
How long do I have to claim missed ITCs?
Most businesses have four years from the due date of the return for the period in which the credit could first have been claimed. Some larger businesses have shorter limits.
How long must I keep GST/HST records?
Generally six years from the end of the year they relate to, under CRA record-keeping rules.
Can an AI agent decide whether a purchase qualifies?
It can apply rules you set and flag uncertain cases. Whether a purchase is used in commercial activities, and restricted items, should be decided by you or your accountant.
Sources
- Spark Receipt: GST/HST input tax credit documentation · accessed Oct 2026
- CRA: Keeping records · accessed Oct 2026
- CRA: GST/HST for businesses · accessed Oct 2026
This article is general information, not financial, legal or tax advice. Products described are provided under the terms on this site and are subject to regulation and eligibility.