When I’m doing financial coaching with a family, I encourage them to do all their budgeting, bill paying, grocery shopping and meal planning only once a month. People usually look at me like I’ve lost my marbles but this is how I run my busy home. It works, it saves a ton of time and it also saves a ton of money. Here’s why: Statistics show that the average American spends about $10 in unplanned, discretionary purchases every time they go to the store. If you go grocery shopping once a week and add in the weekly Target run, that’s at least $80 a month you’re spending that you shouldn’t.