On Friday and Saturday, customers will be able to take any size container to 7-Eleven and fill it up for just $1.50.
Some creative options could be buckets, bottles, or a boot, although some rules do apply.
The container must be leak-proof and no more than 9 inches wide and 11 inches tall.
The promotion also does not allow more than one cup per person, and all containers must be food safe.
"Bring Your Own Cup Day" will apply from 11 a.m. to 7 p.m. on both days.