Why the spreadsheet fails
The spreadsheet has three problems. It is updated after the fact, so a payment that never arrived looks the same as one you have not entered yet. It records the amount you expected, not the amount that came, so a $1,700 transfer against $1,850 rent is easy to mark as paid. And it holds no proof: at an LTB hearing or a CRA review, "the spreadsheet says" is not a record, the bank's notification is.
None of this is carelessness. It is what happens when the record is separate from the money.
This is general information, not legal advice. The rules come from Ontario's Residential Tenancies Act and the Landlord and Tenant Board (LTB). For the current forms and guidance see tribunalsontario.ca/ltb, and speak to a lawyer or paralegal about your own situation.
The email your bank already sends
Every e-Transfer that lands in your account produces a notification email: who sent it, how much, the reference number and the date. If you have auto-deposit on, it says the money has been deposited. That email is the record. The trick is to stop reading it and start forwarding it.
Set a rule in your email (Gmail, Outlook and most bank-linked mailboxes can do this) that forwards every message from the Interac notification address to a second address. That second address is where the tracking happens.
Matching the transfer to the lease
KeyToRental gives you a forwarding address. Every notification that arrives there is read for the amount, the sender's name and the reference, and matched to the lease whose tenant sent it. Wording differs by bank and changes over time, so the parser works from the plain text and is tolerant of the variations; a message it cannot read with confidence is not booked, it is held.
A clean match is recorded as a payment on the ledger with the date the money arrived, and the tenant gets a receipt. Anything that does not match cleanly (a new tenant's first transfer, a sender name that differs from the lease, an amount that is not the rent) lands in an Interac inbox where you confirm which lease it belongs to or reject it. Nothing is booked on a guess.
Partial payments and late rent
Because the ledger records what actually arrived, a $1,700 transfer against $1,850 rent leaves a $150 balance showing, and a transfer that has not arrived by the due date is late the next morning without anyone checking. The day after the due date KeyToRental asks you whether it was paid some other way; if you turn on automatic reminders, the tenant gets one email that day, and you can start an AI reminder call from day 4. If rent is still owing on day 5, the N4 is prepared from the same ledger, with the exact arrears, ready for you to review, print and serve. Nothing is served for you.
Most late rent is a missed transfer and is fixed by one reminder. The point is that you did not have to notice it.
Receipts, and the T776 at tax time
Ontario tenants are entitled to a receipt for rent on request, and a tenant who pays by e-Transfer usually wants one for their own records. Each recorded payment produces one automatically. At year end the same ledger, with the expenses you logged against the property, becomes the T776 tax pack: gross rent by unit, expenses by category, ready for your accountant or your own return. No December afternoon rebuilding the year from bank statements.
Setting it up
Three steps. Add the lease with the rent amount and due day. Set the forwarding rule in your email to the address KeyToRental gives you. Then, when the first transfer from each tenant arrives, confirm it once in the Interac inbox so the sender is linked to the lease; after that, matches are automatic. If you prefer, you can also record a payment by hand, for a cheque or cash, and it sits on the same ledger.