Wholesale VoIP Termination Explained: Rates, ASR, ACD & Billing

VoIP termination is the service of carrying your outbound calls to phone numbers on the public network — mobiles and landlines in other countries. If you run a call center, a dialer or a reseller business, the route you buy decides your call quality and your margin. This guide covers the terms you'll see when comparing providers.

Rate decks and prefixes

Termination is priced per destination prefix. A rate deck lists each prefix — for example 44 for the UK or 447 for UK mobiles — with its per-minute price. The longest matching prefix wins, so a call to a UK mobile is billed at the 447 rate even though 44 also matches.

Billing increments change the real price

• Billing is written as initial block / billing block, such as 60/60, 30/6 or 1/1 (seconds).
• 60/60 means the first minute is charged in full and every minute after that is rounded up — a 61-second call bills as 2 minutes.
• 1/1 bills per second. A higher per-minute rate on 1/1 can work out cheaper than a lower rate on 60/60 for short calls.
• Always compare the rate together with its increments, using your own average call length.

ASR and ACD: reading route quality

• ASR (Answer-Seizure Ratio) — the share of attempted calls that were answered. A sudden ASR drop often means the route is failing or blocking calls.
• ACD (Average Call Duration) — how long answered calls last. Very short ACD on a route can point to poor audio or false answers.
• Track both per destination and per route; a blended average hides a single bad country.

CLI vs CC routes

CLI routes deliver your caller ID to the person you call, which matters when you need callbacks or higher answer rates. CC (non-CLI) routes are cheaper and suit traffic where the caller ID isn't important. Our guide to CC vs CLI routes covers the trade-offs in detail.

Testing a new route

1. 1Start with a small balance and a few hundred test calls to your main destinations.
2. 2Check that caller ID arrives as expected (on CLI routes) and that audio is clear both ways.
3. 3Compare ASR, ACD and cost per answered call against your current provider before moving volume.

HelloPBX publishes per-destination rates with their billing increments in your portal, shows the cost of every call in real time, and lets you fund your balance with Bitcoin or USDT — with no contract or monthly minimum.