Quite a few carriers, and brokers as well, will have a notation on their invoice that interest will be charged after 30 days. Usually the rate is astronomical, something like 2% per month! I don't think that they do this expecting to get paid any sort of interest, but more so in case they have to take a debtor to court. With the interest noted on the invoice, the court might be more inclined to award it, as it was one of the terms of the debt. This is just speculation on my part however. Freight Broker is correct, we too have had many instances where a carrier will accept freight from our firm over another broker, even when the other broker's rate is higher. The carriers have made it clear, that our payment record (30 days from receipt) helps to keep their cash flow healthy, as opposed to waiting 60+ days for an extra few bucks.