You can usually open a 2021 H &R Block T20 file only in H&R Block tax software, not directly in a normal online browser session. H&R Block’s support pages say prior-year returns are opened from the prior-year software or from your online account’s prior-year area, and FileInfo notes that a T20 file is opened with H&R Block Tax Software and can be imported into the 2021 version when starting a return based on prior-year information.

What to do

  1. Sign in to your H&R Block account or the 2021 H&R Block online tax software. H&R Block Canada’s 2021 software sign-in page exists for that tax year, and H&R Block also provides online access to prior-year returns through MyBlock/Prior Years on supported accounts.
  1. Look for a Prior Years , Open Return , or Continue Taxes option. H&R Block’s guidance says prior-year returns can be found from the Taxes tab under Prior Years , while the software version method uses Open Return on the My Taxes screen.
  1. If the file is on your computer, open it in the matching H&R Block desktop software or import it into a 2021 return if the program offers that choice. A T20 file is associated with H&R Block software and is not a generic file type that opens in standard apps.

If it won’t open

  • Make sure you’re using the same tax-year software or a version that supports importing that file.
  • Check whether you saved a PDF copy instead; H&R Block says a prior-year return can be printed from a saved PDF if you have one.
  • If you only need the data and the file is unavailable, H&R Block and the IRS both offer ways to recover prior return information through account access or transcripts.

Simple example

If you have 2021return.t20, install or open the H&R Block software associated with that year, then use the return-opening/import option rather than double-clicking the file in your file manager. That is the path most likely to work for a T20 file.

Note on online access

If by “online” you mean the web version only, the file may not open there unless H&R Block provides that year’s return in your online account. In that case, the desktop software or a saved PDF is usually the practical route.

TL;DR: A 2021 H&R Block .t20 file is typically opened with H&R Block software, not a generic online viewer, and your best path is to sign in to the matching H&R Block account/software and use Prior Years or Open Return.