TFSA overcontributions are usually not caused by people trying to break rules. They often happen because TFSA room is flexible but not real-time: withdrawals return later, institutions report later, and multiple accounts share one combined limit.
This guide explains how excess TFSA amounts happen, why the 1% monthly tax matters, and how to build a safer contribution workflow before depositing new money.
How TFSA overcontributions happen
A TFSA overcontribution happens when total contributions exceed available contribution room. The room calculation includes annual limits, unused carryforward, restored prior-year withdrawals, and contributions made across every TFSA account.
The mistake is often timing. If you withdraw from a TFSA and replace the money in the same calendar year without available room, the recontribution can become excess even though the money previously came from the TFSA.
The 1% monthly tax
CRA guidance commonly describes the excess TFSA tax as 1% per month on the highest excess amount in that month. The penalty can continue while the excess remains. A small excess fixed quickly is very different from a large excess left in place for months.
This page is not a penalty calculator or tax-dispute guide. If you receive a CRA notice or believe an excess exists, use CRA guidance and consider qualified tax help for the correction process.
Mistake 1: recontributing too soon
The easiest way to create an excess is to withdraw money and put it back before the room is restored. Withdrawals generally return as contribution room on January 1 of the following year, not immediately.
If you withdraw $10,000 in July 2026, the clean recontribution date is generally January 1, 2027 or later, unless you already had enough unused room before recontributing.
Mistake 2: relying on stale CRA room
CRA My Account is useful, but it may not include every recent transaction. During the year, your bank or broker may know about a contribution before CRA does. This can make the online number look safer than it really is.
Before a large contribution, reconcile CRA room with your own records and financial institution statements. This is especially important after transfers, withdrawals, or automatic deposits.
Mistake 3: ignoring residency years
A lifetime TFSA room table assumes eligibility for each year. New residents to Canada may not have room for years before becoming resident, even if they were older than 18. This can make generic room estimates too high.
If you moved to Canada after 2009, use your Canadian residency start year in any calculator and verify eligibility before contributing.
A safer contribution workflow
Use a simple process before making a real deposit: check CRA My Account, list every TFSA contribution this year, list prior-year withdrawals that should have restored room, check current-year withdrawals separately, and confirm all institutions are included.
If the estimate is close to zero or your records conflict, pause before contributing. The value of squeezing in one extra deposit is usually not worth the stress of an avoidable excess contribution.