Interac's own answer to the limits question leaves no room for interpretation: "Like most financial transactions, there are limits on the amount you can send. Each financial institution sets their own. Please contact your bank or credit union for details."
Why one limit is usually three
Most banks apply a per-transaction cap, a rolling daily cap and a rolling weekly or monthly cap, and the three interact: a large single transfer can be allowed while a series of smaller ones is refused, or the reverse. Business accounts and personal accounts are treated differently, and a newly opened account frequently carries a lower cap for its first weeks.
Receiving is not the same as sending
Send limits and receive limits are separate settings, and a transfer can fail because of the recipient's ceiling rather than yours. Autodeposit changes the claim step, not the ceiling.
What to ask your bank
Four questions get you the whole picture: what is the per-transaction limit, what is the daily limit, what is the weekly or monthly limit, and can any of them be raised on request. Ask in writing if the answer matters, because front-line answers vary.
How the rail behaves inside a cashier is covered in how an e-Transfer deposit and withdrawal works.
Frequently asked
Who sets my e-Transfer limit?
Your bank or credit union. Interac's own guidance says each financial institution sets its own limits and directs you to ask yours.
Why do I have more than one limit?
Most institutions apply a per-transaction cap alongside rolling daily and weekly or monthly caps, and the three interact.
Can a limit be raised?
Often, on request, and sometimes only after an account has been open for a period. It is worth asking in writing.
Does the recipient have a limit too?
Yes. Send and receive limits are separate settings, so a transfer can fail because of the other side's ceiling rather than yours.