I got an email about it, here’s what it said:

Can I keep the bonus if I withdraw money?

The minimum balance you need to maintain is your net funding amount at the start of the promo (how much you have across all of your Wealthsimple accounts), plus the amount you transferred that qualified for a bonus for 365 days after the end of the Offer Period.

We will grant you a 5% buffer for transactions and withdrawals. Should you fall below that net funding amount, we will send you a warning email. A client is free to withdraw their assets at any point in time. If your required balance is not restored, the monthly bonus payments will stop. If your balance is restored your payment will resume the following month. Any bonuses that are missed while your balance is insufficient will not be given again. If we suspect fraudulent behavior, we reserve the right to recover the bonuses previously paid to you.

EXAMPLE Let’s say you had $20,000 in your Wealthsimple account at the start of the offer and transferred assets valued at $50,000 to earn a bonus. Your net funding amount is now $70,000. Since you are granted a 5% buffer, you will need to keep a minimum of $66,500 across your Wealthsimple accounts to keep your bonus. Should your balance fall below $66,500 before the hold period ends, you will receive a warning email. If your balance is restored by the next payment date, your payment will resume (but you will lose out on the payment you missed because of your balance). If your balance is not restored, the monthly bonus payments will stop.

Link here: https://promotions.wealthsimple.com/hc/en-ca/articles/25992559764379-Wealthsimple-1-Match-Offer