AC2 File

What are AC2 files and how to open them

Are you having problems opening an AC2 file or are you simply curious about its contents? We're here to explain the properties of these files and provide you with software that can open or handle your AC2 files.

What is an AC2 file?

An .AC2 file is a Banana Accounting Data file.

Banana Accounting Data files (extension AC2) are the native data files used by Banana Accounting (also known as Banana Accounting+, Banana.ch's accounting software). They store all parts of one accounting dataset - company structure, chart of accounts, transactions (including recurring and budget items), opening balances, VAT or sales tax codes, exchange rates, and other bookkeeping details - in a single proprietary file.

These files are created and edited only by Banana Accounting. Saving happens via Save or Save As commands; automatic backups (*.autosave) may be generated between manual saves. AC2 files are cross-platform: a file saved on Windows can be opened on macOS or Linux without conversion. Files can be password protected. In a multi-user or cloud-synced setting, only one user at a time can write to the file; if in use elsewhere, the software opens it read-only.

Within internal inspection, AC2 files use a binary structure with fixed-offset identifiers. For example, bytes at specific offsets include zero bytes at offset 1, ASCII "..d" starting at offset 6, a pattern 0x01000000000000 at offset 13, further zero padding, and a distinctive sequence "N" near offset 78, along with bytes 0xFF at offsets 121 and 123.

How to open AC2 files

Important: Different programs may use files with the AC2 file extension for different purposes, so unless you are sure which format your AC2 file is, you may need to try a few different programs.

While we have not verified the apps ourselves yet, our users have suggested four different AC2 openers which you will find listed below.

Last updated: August 16, 2026

Various apps that use files with this extension

These apps are known to open certain types of AC2 files. Remember, different programs may use AC2 files for different purposes, so you may need to try out a few of them to be able to open your specific file.

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File.org helps thousands of users every day, and we would love to hear from you if you have additional information about AC2 file formats, example files, or compatible programs. Please use the links below or email us at submit@file.org to discuss further.