Call routing is the process that decides which buyer a specific inbound call is offered to, and where it rings once that decision is made. In a marketplace with many buyers and many publishers, routing is the layer that connects the right call to the right buyer at the right moment.
The path a call takes
- 01A call arrivesA consumer dials a number tied to a publisher's traffic source.
- 02The marketplace evaluates eligibilityIt checks which buyers currently have the matching campaign switched on and are available to receive calls.
- 03A buyer is selectedThe call is matched to a buyer based on campaign, availability, and any other delivery rules in place.
- 04The call is deliveredIt rings the buyer's chosen destination, whether that is a phone number, a SIP address, or the browser softphone.
What decides which buyer gets a call
- Whether the buyer has that specific campaign switched on.
- Whether the buyer has their availability toggle turned on right now.
- Whether the buyer has room left under any daily call limit set for that campaign.
Availability is a real-time signal
A buyer switches availability on and off, and when it is off, calls are not delivered to that buyer at all. This is separate from per-campaign toggles, which control which types of calls a buyer wants even while generally available. Both controls exist so a buyer only receives calls they are actually staffed and ready to take.
Where a call can be delivered
Calls can be delivered to a phone number, technically called a DID, or a SIP address the buyer designates, or answered directly in the Callmart browser softphone. See destination numbers for how buyers set and manage where calls land, and sip vs pstn for the technical difference between the two connection types.
Routing for wholesale buyers
Wholesale buyers can have Callmart ask their own system before each call is delivered, a step called buyer preacceptance ping. Their system gets a short window to accept or deny a proposed call before it is routed to them. This is documented in full in the wholesale ping setup guide.
What happens when no buyer is currently eligible
Routing depends on real-time conditions: which buyers have a matching campaign switched on, are currently available, and have room left under any daily limit. When no buyer meets all three conditions at the moment a call arrives, that call cannot be routed to anyone, regardless of how good a match it might have been under different timing. This is part of why availability and per-campaign toggles matter as much as which campaigns you select in the first place.
Why routing rules are set at the marketplace level, not per call
A marketplace with many publishers and many buyers cannot practically negotiate routing terms call by call. Instead, the rules are set in advance, campaign by campaign: what qualifies a call for a given campaign, which buyers are eligible to receive it, and what pricing and buffer apply once it is delivered. A buyer's job is to configure their own side of those rules correctly, through campaign toggles, availability, and destinations, rather than to negotiate an individual call's terms after the fact.
| Setting | What it controls |
|---|---|
| Availability toggle | Whether you receive any calls at all right now |
| Per-campaign toggle | Whether you receive calls for a specific campaign |
| Daily call limit | How many calls you receive on a campaign within a day |
None of these settings change the price or buffer for a campaign. They only change whether and how often a call reaches you, which is a separate decision from what a call costs once it does.
Common questions
01Can I control which calls get routed to me?
Yes, through per-campaign toggles, your overall availability switch, and any daily call limits you set. Routing only offers you calls that match what you currently have switched on.
02What happens if I switch my availability off?
Calls are not delivered to you while availability is off. You will not be routed calls until you switch it back on.
03Can a call be routed to more than one buyer at once?
Routing selects a buyer for delivery based on the rules in place at that moment, such as campaign and availability. Concurrency and caps covers how multiple simultaneous calls are handled on your end once routed.
04Where can routed calls ring?
A phone number (DID), a SIP address you designate, or the Callmart browser softphone, depending on what your account has set up.