Which sentence is correct?

Use the calculator to determine how many days delinquent the loan is.

Use the calculator to determine how many days the loan is delinquent.

I thought there was a rule about ending a sentence with "is".

Thank you!

Quote: I thought there was a rule about ending a sentence with "is".

"Ask Mr. Smith. He'll know what kind of bird it is."

Both of your sentences are fine. The first sounds more like what a loan clerk would say!