The IRS has begun mailing letters to tax payers with the IRS ID PIN for the 2020 tax year. If you have been issued an ID PIN in the past you will need this PIN to E-File your 2020 tax return. When you get it make sure you give the number to your tax preparer so he or she can include it on your tax return. If you lose the ID PIN you will have to either contact the IRS to issue a new ID PIN or you will have to mail in your tax return which would delay your receipt of your 2020 refund.