If I write a check for 15¢, can the recipient cash or deposit it?
Back in the 1980's when I was in college I had to write a check to the State of Maryland because I owed less than a dollar with my tax return. At that time the was no requirement to forgive amounts less than a dollar. There was no requirement to round all the boxes on the tax return. I don't recall the exact amount, but I remember that the stamp cost more then the check amount.
At some point the recipient might decide the amount was too small to be worth the effort to scan the check and submit it.