According to the Ohio Revised Code: "...on or before the twenty-third day or each month (each person who has...a vendor's license shall...) make and file a return for the preceding month, on forms prescribed by the tax commissioner."
"The return shall be considered filed when received by the treasurer of the state... The treasurer of the state shall stamp or otherwise mark on all returns the date received... and shall also show thereon...the amount of payment received with the return."
Returns must by filed even if no sales are made and/or tax collected. If a vendor does not file a return, the Department of Taxation may revoke a license because of inactivity.