Is the cheaper gas worth the drive?

Warehouse gas is often cheaper per gallon. But a long detour burns some of what you save, and so does a long line. Plug in your numbers.

Gallons per fill-up

gal

How much cheaper per gallon (compare the warehouse price with your usual station)

Fill-ups per month

/mo

Extra miles, round trip (beyond the drive to your usual station; 0 if it's on your way)

Your car's miles per gallon

mpg

Gas price per gallon (roughly what you pay now)

Extra minutes per trip (detour plus waiting in line)

min

What your time is worth per hour (optional; leave at 0 to ignore time)

Enter your numbers above.

Saved at the pump, per fill-up$0

Cost of the extra driving, per fill-up$0

Value of your extra time, per fill-up$0

Net per fill-up$0

Net per year$0

Longest detour that still saves money0 mi

Not sure how far away the nearest one is? Find Costco gas stations near you.

How the math works

Pump savings = gallons per fill-up times the price gap per gallon.
Driving cost = extra miles divided by your miles per gallon, times the price of gas.
Time cost = extra minutes, as a share of an hour, times what you say your time is worth.

Net savings are the pump savings minus the other two, then multiplied by your fill-ups per month and by 12.

Tips for saving more

Fill up when you're already shopping. If the trip is happening anyway, the extra miles are close to zero.
Go when lines are short. Lines are usually longest at busy shopping times, which eats into the value of your time.
Check the gap, not just the price. A station a few cents cheaper next door can beat a bigger gap across town.

Does this cover the membership fee?

You need a membership to buy gas at the warehouse. If gas is your main reason to join, compare your yearly gas savings here with the $65 Gold Star fee. Our membership calculator covers the rest of your shopping.

Last reviewed October 18, 2026.