The only way to know if the IRS got a mailed return is if you got a tracking number from the post office. Or they cashed your check if you included one for a tax due. Or you receive the refund. Or if it shows up here, 4 weeks after mailing you can start checking IRS Where's my refund
https://www.irs.gov/refunds/
But they are not processing mailed returns right now.
See this IRS page for the latest information.
https://www.irs.gov/newsroom/irs-operations-during-covid-19-mission-critical-functions-continue
It says.......
Paper Tax Returns: All taxpayers should file electronically through their tax preparer, tax software provider or IRS Free File if possible. The IRS is not currently able to process individual paper tax returns. If you already have filed via paper but it has not yet been processed, do not file a second tax return or write to the IRS to inquire about the status of your return or your economic impact payment. Paper returns will be processed once processing centers are able to reopen. This year, more than 90% of taxpayers have filed electronically.
