If I have a $50 promo GC, but spend less than that in an order, I'm assuming the remaining balance stays in my account. However, if I place another order later, can I add another promo GC with the remaining balance or do I need to use up the entire balance before I can apply another promo GC?

I wish I had problems like this.

Yes.. you can combine promo gc's with regular gc's in multiple orders. You just can't have more than one promo gc in each order.

And yes, if you go in to buy something, you'll see your leftover GC balance in your account.

Hi Ben732,
I understand that promo and non-promo GCs can be combined in an order and also that a leftover balance will remain in the account. However, my question is if the leftover balance came from a promo GC, can I combine this balance and another promo GC in a new order?

No.. but usually the promo gc would be used on an order before the other GC, so your normal GC should have a higher balance...

If you added a promo GC to your gift cert balance one day but didn't use it, and then came back 3 days later to buy something and tried to add another promo gc, it wouldn't let you.

But like I said, your GC balance is probably from your regular GC and not from the promo. I'm no expert, but thats the way I've seen it work for me in the past.