How long does a mailed tax return take to get a check back? How do you know if a mailed tax return os accepted?

The IRS states it can take 4 weeks after mailing your paper return for it to begin processing.  Paper-filers: The IRS asks you wait 4 weeks after you mail your return before looking up your refund at Where's My Refund?

The only way you will know sooner if a mailed tax return got to the IRS is to use a mailing service that will track it like certified mail or UPS so you know the IRS received it.