What is A-Z termination?
A-Z termination means a carrier can complete calls to virtually every country and number type in the world — fixed, mobile and special ranges — through one interconnect. Instead of contracting a separate provider per destination, you send all outbound traffic to one wholesale partner who routes it onward.
Rates are published in a rate deck: a spreadsheet listing every destination, its dialing prefixes and a per-minute price.
How a rate deck is structured
- Destination name — e.g. "Mexico Mobile Telcel" or "UK Fixed".
- Dial codes — the prefixes that identify the destination. The longest matching prefix sets the price.
- Rate — usually in USD per minute, often to four or more decimals.
- Effective date — when a new rate applies. Increases normally require advance notice (commonly 7 days).
- Billing increment — for example 1/1, 6/6 or 60/60 seconds.
Why mobile costs more than fixed
In many countries mobile operators charge higher termination fees than fixed-line operators. That cost is passed through, so mobile destinations are frequently several times the price of fixed ones in the same country.
Billing increments matter as much as the rate
A route billed 60/60 rounds every call up to the next full minute; 1/1 bills per second. On short-duration traffic such as call centres, a slightly higher per-second rate can cost less overall than a cheaper per-minute rate.
How to compare carriers fairly
- Compare against your real traffic mix, not headline prices.
- Check route quality: ASR, ACD, post-dial delay and CLI delivery.
- Confirm how often rates change and how notices are delivered.
- Ask about minimum commitments, prepayment and credit terms.
- Run test traffic before committing volume.
Frequently asked questions
What is a wholesale A-Z rate deck?
A spreadsheet listing every destination a carrier terminates, with its dial codes, per-minute rate, billing increment and effective date.
Why do termination rates change so often?
Underlying operator costs, currency movements and route availability shift constantly, so carriers update decks regularly with advance notice for increases.
Is per-second billing always cheaper?
Not always, but for short average call durations per-second (1/1) billing usually lowers total cost compared with 60/60 billing.