The trick for billing big companies (those with a separate accounts payable division) is to incentivize early payment (say with a 5% discount). Most account pay

The trick for billing big companies (those with a separate accounts payable division) is to incentivize early payment (say with a 5% discount). Most account payable divisions will always try and pay the lowest amount, so they will pay early to receive the discount. Of course you bump up your rate in initial contract negotiations to make up for the discount.