A call buffer is a minimum connected-time threshold. On Callmart, a completed call is billed once if its connected duration reaches or exceeds the selected buffer. The charge is finalized after the call ends, when its duration is known. Ringing before your destination answers does not count.
Try the call buffer calculator
Illustrative inputs. Replace them with your own figures. Calculations stay in this browser; no account is needed.
Reaches the billing threshold
15 seconds in your answering system + 45 seconds of conversation = 60 connected seconds. The 20 seconds before answer are excluded.
At 60 connected seconds the threshold is met, including at exactly 60. This models the duration rule only; actual charges follow your approved campaign terms and call record.
Not countedSystem answers
Clock startsCall ends
Threshold met
This is a billing example, not a live call record. The selected buffer does not hold callers upstream until they qualify. Calls can reach your team and use time even when they end before the billing threshold.
Exactly what counts toward the buffer
| Part of the call | Counted? | Why |
|---|---|---|
| Ringing before your destination answers | No | The destination has not connected. |
| Your IVR, queue greeting or voicemail after answer | Yes | Your phone system has answered, even if an agent has not spoken. |
| Conversation after answer | Yes | The call is connected to your destination. |
| Time before the call reaches your destination | No | Use the buyer destination leg, not the caller's entire journey. |
A 60-second buffer, three outcomes
| Connected duration | Threshold result | Call charge |
|---|---|---|
| 59 seconds | Below 60 seconds | Not billed under this duration rule |
| Exactly 60 seconds | Meets the threshold | Billable at the agreed call price |
| 90 seconds | Exceeds the threshold | One call charge, not a second charge at 90 seconds |
Choose a tier using your own call records
Callmart has a 10-second minimum buffer. Available campaigns can have different price and duration tiers. Review the actual pair in your approved workspace; a public starting price is not a quote for every tier, state or campaign.
A longer buffer changes which connected calls qualify for a charge. It does not establish that a caller is eligible, interested, exclusive or likely to buy. It also does not remove the staff time spent on short calls. Compare total billed spend, all agent time and acquired customers for a consistent group of calls before changing tiers.
If your destination uses a greeting or voicemail, inspect where the answer event occurs. Fifteen seconds in your answering system plus forty-five seconds of conversation equals sixty connected seconds. Treating only the conversation as billable duration would produce a different, incorrect result in that example.
Buffer can mean something else in a call center
In this guide, buffer means a pay-per-call billing threshold. A team may use the same word for spare staffing capacity, time between calls or a technical audio buffer. Those are different measurements. When comparing an offer, ask which leg starts the clock, what counts after answer, the exact threshold and the price attached to it.
Common questions
01Is a call at exactly the buffer billable?
Yes. The duration rule is greater than or equal to the selected buffer. A completed call at exactly 60 connected seconds meets a 60-second buffer.
02Does a longer buffer stop short calls reaching my agents?
No. It changes billing qualification after answer. A short call may still ring, connect and consume agent time without reaching the threshold.
03When does the charge appear?
The call charge is finalized after the call ends and the connected duration is known. A wallet hold or pending call is different from a finalized charge.
04Does voicemail count?
Time after your own destination answers can count, including time in voicemail or an IVR. A human greeting is not required to start the connected-time clock.