A BA9 file contains a backup of a tax return created by the 2019 version of TaxAct, a tax-preparation program for the 2019 tax year. It stores 2019 tax data, which includes federal IRS and state tax form data along with basic personal information, such as the name and occupation of the user. BA9 files are used for archival purposes and as a backup to the .TA9 tax return file in the event that it is lost or becomes corrupt.

You most likely will only encounter a BA9 file if you file your taxes with TaxAct 2019 software. Each annual release of TaxAct uses a different extension for backup files. For example, a tax return backup file created by TaxAct 2017 uses the .ba7 extension, while TaxAct 2018 creates backup files with the .ba8 file extension. BA9 files may be created manually by a user or automatically generated by TaxAct 2019. To manually save a backup of your tax return with TaxAct 2019, select File → Backup... and name your file. You must save your tax return as a TA9 file before creating your backup. To restore a backup in TaxAct 2019, select File → Restore Backup... and navigate to the location of your BA9 file. TaxAct 2019 automatically generates three types of BA9 tax return backup files and stores them in the "AUTO-BACKUP" folder. The three types are the current backup, a daily backup, and a weekly backup. You can tell the type from the filename. For example, the daily BA9 backup file for a 2019 tax return is .ta9_daily.ba9.