What does *66 do to your phone?

What Does *66 Do on Your Phone?

If you've ever tried calling someone only to get a busy signal, you're not alone. Back in the days of landlines, this was a common frustration—especially when trying to reach customer service, a doctor's office, or a popular hotline. That's where *66 comes in.

*66 activates the Auto Redial feature on many landline and some mobile networks. When you dial a number and get a busy signal, you can hang up, then press *66 to set your phone to automatically redial that number. It keeps trying every few seconds for up to 30 minutes. The moment the line clears, you'll get a special ring or tone to let you know you're through—no more manually pressing redial over and over.

This feature was especially useful before voicemail and call waiting became widespread. It saved time and gave callers an edge when trying to break through congested lines. While less common today thanks to smartphones and digital communication, *66 is still supported by some landline providers, particularly in rural areas or older systems.

Fun fact: if you were using a rotary phone back in the day, you’d have to dial 1166 instead—rotary phones didn't have asterisks, so sequences like 11XX were used as substitutes.

Though modern messaging and calling apps have made Auto Redial feel like a relic, it was one of the earliest forms of automated convenience in telephony. Next time you're stuck in a call loop, you might appreciate the simplicity of *66—even if you don't use it much anymore.