Termination, in plain terms
"Termination" is telecom shorthand for delivering a call to its final destination — the call "terminates" there. A wholesale VoIP termination provider takes calls handed to it over SIP (from a PBX, predictive dialer, another carrier, or an AI voice platform's SIP trunk) and routes them across the phone network to the number dialed, charging per minute against a published rate.
What "A-Z" means
An A-Z rate deck covers every destination the provider terminates to — potentially hundreds of countries and thousands of distinct prefixes (country + operator/region combinations), each priced individually. A reseller or high-volume buyer typically wants A-Z coverage from one or a small number of providers rather than negotiating a separate deal per country.
How pricing actually works
- Per-minute rate — the headline price, usually in USD, for a specific destination and route type.
- Billing increment — how the connected duration is rounded for billing (1/1, 6/6, 60/60, etc.) — see billing increments explained. This can matter as much as the headline rate for short-call traffic.
- Effective dates — wholesale rates change; a rate deck lists an effective date, and providers should be transparent about upcoming changes rather than only current ones.
- Route type — the same destination is often priced differently for different traffic types (e.g. general outbound vs. Press 1 broadcast), and for CLI vs Non-CLI routes — see CLI vs NCLI explained.
Tier-1 / direct routes vs. indirect routes
Some routes connect through a direct interconnect with the destination country's incumbent or a major carrier ("tier-1" or "direct" routes); others pass through one or more intermediate carriers ("indirect" routes). Direct routes generally cost more and tend to offer more consistent quality (ASR, ACD, PDD); indirect routes are cheaper but quality can vary more, and can change without notice if the intermediate carrier's own upstream changes.
How this differs from a retail phone/PBX plan
A retail hosted-PBX or phone plan bundles a fixed number of minutes or an "unlimited" allowance into a flat monthly fee, aimed at a single business's own phone system. Wholesale termination is priced per minute at bulk rates, aimed at businesses and resellers who need to route real volume — call centers, dialers, other VoIP providers reselling capacity, and increasingly AI voice platforms needing a carrier layer (see AI Voice SIP).
Who actually buys wholesale VoIP termination
- Call centers running outbound or Press 1 campaigns at volume.
- VoIP resellers and white-label providers who need underlying carrier capacity.
- AI voice platforms and their customers connecting via BYOC.
- Businesses with their own PBX/dialer who have outgrown a retail plan's pricing or capacity.
Where to start
See Wholesale VoIP for current A-Z coverage and live rates for published destination-level pricing, or request a route test before committing volume.