Customizing Bash Prompt with PROMPT_COMMAND

How to customize your terminal prompt using the PROMPT_COMMAND environment variable in Bash

February 19, 2026

In Bash, the PROMPT_COMMAND environment variable allows you to execute specific commands just before a new prompt is displayed.

This allows you to display a real-time Timestamp or custom information in your terminal prompt.

For example, entering the command below will display the current date and time before the prompt.


Set PROMPT_COMMAND
sh

To ensure the settings persist even after restarting the terminal, you must add them to your ~/.bashrc file.


~/.bashrc
sh

You can use ANSI Escape Codes to add color and keep the prompt from looking cluttered.


Colorful Prompt
sh

To clear the PROMPT_COMMAND you set and return to the default state, use the unset command.


Unset PROMPT_COMMAND
sh

While you can also decorate the prompt by modifying the PS1 variable, PROMPT_COMMAND is more powerful in the following situations:

Executing complex logic: Beyond simply showing text, you can run specific scripts or record logs.
Dynamic information update: Suitable for calculating and showing the number of files in the current working directory or Git branch status in real-time.