Your first problem is you are mailing in paper copies of the forms. It is2018 do it electronically so you know the forms were filed on time you knowthey went to the right place and you reduce the risk of human error inprocessing.Although the addresses are similar go to the same processing centers and theIRS is probably capable of getting your form to the right processing pointwithin that center I don’t recommend you mail the two form to the sameaddress as there are slight differences in P O boxes andor zip codes for 941and 940 forms. Those slight differences send the respective envelopes todifferent processing points at each IRS center.If you want your return processed in a timely manner send it to the exactaddress in the instructions.941 Scroll to page 5 for the address httpswww.irs.govpubirspdf...940 Scroll to page 4 for the address httpswww.irs.govpubirspdf...