Understanding 1/1, 6/6, 60/1 and 60/60 Billing

What the notation means

A billing increment is written as initial/recurring seconds — the first number is the minimum charge for connecting the call, the second is how the remaining duration is rounded.

The four common increments

• 1/1 — one-second minimum and one-second increments. The most granular; you pay close to the exact connected duration.
• 6/6 — six-second minimum and six-second increments. Duration is rounded up to the nearest 6 seconds.
• 60/1 — the first 60 seconds are charged as a block, then billing switches to one-second increments.
• 60/60 — calls are charged in complete 60-second (whole-minute) blocks, rounded up.

Why it matters

For short calls, 60/60 billing charges a full minute even if the call lasted a few seconds, which materially changes the effective cost per call compared to 1/1 or 6/6 billing at the same headline rate per minute.

Where to check it

Every published rate on the VoIP Rate Comparison page and in the CSV export states its billing increment. The cost calculator applies the correct increment automatically when estimating a call or campaign cost.