I recently wrote a comparison piece on Staples' Ink Cartridge Return Policy vs. that of Office Depot. In it, I point out the lag time between trading those inks in and when you actually see your reward. Staples is currently sends ink rewards out once a month, if you've reached $10 in rewards. Office Depot is closer to 4-6 weeks before your returns are credited to your account.
So don't hold your inks any longer than you have to! Turn them in as soon as possible to get those rewards back in time for Back to School. I know... school has just let out! But the summer will fly by fast and before you know it, you'll be shopping for pencils, pens and notebooks.