Mobile banking apps make depositing cheques easy, and they make accidental double deposits just as easy. The most common case: you deposit a cheque in your bank’s app, forget you did, then deposit the paper cheque at an ATM or branch the next day. This page covers what happens next and how to handle it; other account problems are in the banking security hub.
Why both deposits can show up at first
Canadian cheques clear electronically: your bank captures an image of the cheque and sends it through Payments Canada’s clearing system. Duplicate detection isn’t instant, so both deposits can appear as pending, or even credited, before one is flagged and reversed. How clearing and deposit holds work is covered in how long a cheque takes to clear.
What happens when a duplicate is detected
- Both deposits credited at first: depending on your bank’s hold policy, funds may appear in your account from both deposits
- Duplicate flagged: the clearing system or your bank’s internal controls identify the duplicate image, usually within 1–3 business days
- One deposit reversed: the bank reverses one of the deposits, typically the second one received chronologically
- Your account is debited: if the duplicate funds were spent, the account may go into overdraft (how overdraft protection works)
- A fee may apply: a returned item fee ($5–$15 typical) may apply to the reversed deposit
The cheque issuer’s bank honours the cheque only once: the payer’s account is debited for the correct amount.
What to do
Step 1: Tell your bank
Calling the number on the back of your debit card, or visiting a branch, before the bank finds the duplicate itself puts the error on record. Each bank’s line is on its page in the bank customer service directory.
Most banks treat a first-time honest error differently from deliberate fraud. Contacting the bank first:
- Stops them from treating it as suspicious activity
- May result in fee waivers
- Accelerates the reversal process so your balance is corrected faster
Step 2: Leave the duplicate funds alone
A higher-than-expected balance will shrink when the reversal comes through. If the duplicate money has been spent by then, the account goes overdrawn, which can mean overdraft fees on top of any returned item fee.
Step 3: Mark the physical cheque
Writing “MOBILE DEPOSITED: DO NOT DEPOSIT AGAIN” across the face of the paper cheque prevents a third attempt. Keeping it for about 90 days helps if the bank needs to review it; some banks ask you to destroy the paper cheque after a set period following a mobile deposit, which their mobile deposit terms spell out.
If you deposited at two different banks
This happens when someone receives a cheque into an old and a new account, or transfers accounts between institutions. The scenario:
- You deposit the cheque at Bank A
- Bank A credits your account and submits the image to the clearing system
- You deposit the physical cheque at Bank B (days later)
- Bank B also submits the image
- The duplicate is detected: Bank B receives a return and debits your account for the full amount
Both banks need to hear about it, so each can flag the account for the incoming reversal. Bank A’s deposit usually stands as the valid one, and Bank B reverses its deposit.
Can this be treated as fraud?
Accidental double-depositing breaks the terms of your account agreement and Payments Canada rules, but honest mistakes are handled very differently from intentional cheque kiting. Intentional double-depositing (depositing the same cheque at multiple institutions knowing the duplicate will go through) is cheque fraud under the Criminal Code of Canada.
Your bank will consider context: first-time customer, proactive self-reporting, small amounts, and no pattern of similar behaviour. If you call before they catch it, the situation almost always stays in the “administrative error” category.
Common double-deposit scenarios
| Scenario | What happened | Fix |
|---|---|---|
| Mobile deposit + ATM deposit same cheque | App deposit forgotten | Call bank, mark physical cheque |
| Mobile deposit + branch deposit | Same cheque deposited days apart | Call bank before branch deposit clears |
| Old account + new account at different banks | Received cheque before switching banks | Contact both banks |
| Cheque deposited, returned NSF and re-deposited, then the original also deposited again | Tracking confusion | Confirm with the payer whether the cheque was reissued or redeposited |
Avoiding it next time
- Writing the date and “MOBILE DEP” on the face of a cheque right after a mobile deposit marks it as used.
- A separate envelope labelled “deposited, do not use” keeps mobile-deposited cheques apart from new ones.
- Most banks send a mobile deposit confirmation right away, which is a quick check before depositing a paper cheque.
For other banking errors, see what to do when an e-Transfer bounces, how to cancel a bank transfer and, for a cheque that bounces the other way, what happens if you write a bad cheque.