How to Completely Disable the ‘Startup Disk’ (Boot Picker) Delay on a Mac

If you are dual-booting your Mac with Windows via Boot Camp, or if you frequently boot from an external Thunderbolt drive containing a different version of macOS, you are intimately familiar with the Mac “Boot Picker” (accessed by holding the Option key on Intel Macs, or holding the Power button on Apple Silicon Macs). However, some advanced users who frequently switch operating systems use third-party boot managers (like rEFInd) or simply rely on the NVRAM to select their boot disk.

When you use the official Apple Startup Disk utility to switch partitions, macOS sometimes injects a slight, invisible delay into the firmware before the bootloader actually executes. This ensures the firmware has enough time to poll for connected Bluetooth keyboards holding the Option key. If you never use the native boot picker and want your Mac to boot from the NVRAM-designated default drive as fast as physically possible, you can completely disable this firmware polling delay.

Disabling the Boot Picker Delay via Terminal (NVRAM)

Because this is a low-level firmware setting, you cannot change it from the standard macOS System Settings. You must use the Terminal to write a new variable directly to the Mac’s Non-Volatile Random-Access Memory (NVRAM).

1. Open the Terminal application on your Mac (you can find it in Applications > Utilities, or by searching Spotlight).
2. You need to alter the StartupDelay variable. Type the following command exactly as it appears and press Enter:
   sudo nvram boot-args="StartupDelay=0"
3. The terminal will prompt you for your administrator password. Type it in (the characters will not appear on screen) and press Enter.
4. (Note: If you already use other custom boot arguments, like verbose mode, you must include them in the quotes as well, e.g., sudo nvram boot-args="-v StartupDelay=0", otherwise they will be overwritten).
5. Close the Terminal and restart your Mac.

Upon restarting, the firmware will completely skip the polling delay. The Mac will instantly grab the default boot volume from NVRAM and begin loading the operating system without waiting to see if you are pressing any keys on your keyboard.