should i do it here in canada or wait until we get to the US?

I would do it in Canada- there are many places in the US where it is difficult to get it changed - unless its a large city with a bank that has an international dept- but even then, sometimes they send it away to another site -
It seems to be easier in the border towns- but once you get a little south its very difficult - I have pots of Canadian change and no place to get it changed into US-

Change only a tiny bit before you leave - if you really must. Otherwise - just use your credit card for big expenses and pull cash from your ATM for walking around money. this is much cheaper - and also simpler than changing actual cash.

Listen to nytraveler.

Use your credit card for most purchases and your ATM card to withdraw the cash you need for the rest.

Keith

The ATM is the way to go these days. Call your bank to see if they have any agreements with American banks for ATM use without fees.

If you have 2 bank accounts associated with your debit card, you usually can only access the 1st account. This is what I have found travelling from Canada to the U.S. Check with your bank first.