Wholesale SIP trunking. Carrier rates, no middleman.

Retail trunks are packaged for end users: per-seat plans, bundled features, office-scale volume, and support that assumes the buyer has never read a SIP trace. Wholesale strips all of that out. You get raw carrier capacity at tiered per-minute rates, billed 12/6, with unlimited concurrent channels and no per-channel, setup, porting, or platform fees. If you are provisioning phones for one office, retail SIP trunking is the right product. If you are moving hundreds of thousands of minutes a month, wholesale is.

Who buys wholesale SIP? ITSPs building their own voice products on carrier capacity. Resellers and MSPs who sell under their own brand and keep the customer relationship. PBX integrators provisioning trunks across dozens of client systems. Dialer shops running Asterisk and VICIdial at volumes where a tenth of a cent per minute is real money. Most wholesale SIP trunk providers serving these buyers are aggregators — two or three hops removed from the switch that actually terminates the call. Every hop adds margin and subtracts accountability. Buying from SIPNEX removes the hops.

The credentials behind the trunk are the carrier's own. SIPNEX holds direct FCC authorization, files FCC Form 499, signs every call with its own STIR/SHAKEN SP-KI certificate for A-level attestation at every tier, is registered in the Robocall Mitigation Database, and is a registered RespOrg. The full carrier-services picture — termination, origination, DIDs, peering — lives on the wholesale VoIP page. If all you need is outbound minutes, SIPNEX also operates as a wholesale SIP termination provider — see wholesale voice termination for termination-only detail.

Pricing at SIPNEX is volume-tiered and published. No quote gate, no NDA, no "contact sales to see a number." Rates start at $0.025-$0.030 per minute at the entry tier and step down to $0.005-$0.008 per minute at 10 million or more monthly minutes:

• Entry tier — under 100,000 minutes/month: $0.025-$0.030 per minute
• Top published tier — 10M+ minutes/month: $0.005-$0.008 per minute
• Above 10M minutes/month — custom pricing
• Billing increments — 12/6 (6-second steps after a 12-second minimum)
• Per-channel, setup, porting, and platform fees — none

Tier assignment is automatic. We meter your actual monthly usage and apply the matching rate — cross into a higher tier and the better rate applies without renegotiation, without a contract amendment, without a call to an account manager. Concurrent channels are unlimited at every tier, so concurrency never shows up as a line item. The current tier table is on the published volume-tier pricing page.

Every trunk ships with the full carrier feature set. Nothing below is an add-on, an upsell, or a higher-tier unlock:

• A-level STIR/SHAKEN attestation — signed directly with SIPNEX's own SP-KI certificate, at every volume tier
• Unlimited concurrent channels — no caps, no per-channel fees
• G.711u native pass-through — with G.729 fallback for bandwidth-constrained links
• Sub-3-second average PDD — calls start ringing while slower routes are still setting up
• 24-hour trunk provisioning — with same-day DID provisioning for most orders
• CNAM registration — included with every DID
• Nationwide US DID inventory — with bulk DID volume discounts

Most SIP trunking solutions are packaged around a single workload — an office phone system, a call center seat, an API. Wholesale capacity is workload-agnostic, because the Session Initiation Protocol (SIP) is the common signaling layer under nearly every modern voice product. Unified communications suites bundle voice with other communication channels — messaging, video, presence — but the voice leg still rides a trunk. The communications platforms you build or resell decide the feature set; the trunk underneath decides whether the call connects fast and sounds right.

Contact centers are the demanding case. Outbound campaigns burst to hundreds of simultaneous calls, inbound queues live and die on call routing, and agents hear a dip in call quality before any dashboard graphs it. This is where the trunk spec earns its keep: unlimited concurrent channels absorb the bursts, G.711u pass-through keeps audio unprocessed end to end, and sub-3-second post-dial delay keeps agents talking instead of listening to silence. Fewer dead-air seconds and fewer dropped calls register as customer satisfaction on the other end of the line.

For resellers, the wholesale layer is what makes the retail pitch work: business communications that complete more calls for less money. The cost savings come from tier math rather than corner-cutting, which keeps reselling this capacity cost-effective as volume grows. Aggregators advertise global reach — every country on one rate card — by stitching together other carriers' routes; SIPNEX runs the opposite model, keeping its voice services US-focused and close to the switch that terminates them. Package the trunks as your own SIP trunk services, and every phone number you provision ships with CNAM registration included.

White-label is not a special program bolted onto these trunks — it is how they are designed to be used. You buy wholesale SIP capacity at tiered carrier rates, set your own retail rates, and sell under your own brand. Your customers see your name on the invoice, your portal, your support line. SIPNEX stays invisible underneath: the switch, the attestation, the rate deck.

The margin math works because nothing structural eats it. No platform fees. No per-channel fees. No long-term contract holding you to volumes you have not hit yet. And because SIPNEX signs with its own SP-KI certificate, your end customers' calls carry A-level attestation — a claim most resellers cannot make, because their upstream is itself a reseller. The commercial structure for building on SIPNEX capacity is documented in the VoIP reseller program. At 1 million minutes per month and above, direct SIP peering between your switch and ours is available.