2P SMS remains one of the highest-margin service lines a mobile network operator runs. Industry analyst estimates put the global A2P business in the $70–80 billion range, and per-message termination rates in most international corridors have risen steadily since 2022. But the volume side of the curve has flattened: OTP traffic is being displaced by flash calls and silent network authentication, marketing traffic is migrating to OTT channels, and enterprises audit their messaging spend with a rigour that did not exist five years ago. In that market, the monetisation question changes shape. It is no longer 'how do we start charging for A2P' — nearly every operator does. It is 'of the A2P revenue this network is contractually and regulatorily entitled to, how much actually arrives' — and for most networks the honest answer is somewhere between 60% and 85%. This piece maps where the rest goes.
The seven leaks, side by side
| Leak | Mechanism | Typical impact | Primary control |
|---|---|---|---|
| SIM-farm termination | A2P delivered as retail P2P through consumer SIM banks | 5–20% of entitled A2P revenue | Behavioural firewall + SIM-box detection |
| Partner re-injection | Multi-hop aggregator chains land traffic on cheaper interconnects | 3–10% | Route audit + bind-level sender attribution |
| SS7 injection | MT-ForwardSM pushed straight to the MSC, bypassing the SMSC | 2–8% | Signalling firewall with SRI-SM correlation |
| Category arbitrage | Marketing traffic declared as transactional to ride the lower rate | 2–6% | Content classification at the boundary |
| Unregistered sender IDs | Traffic with no registered originator billed at legacy blended rates | 1–5% | Sender-ID registry enforcement |
| AIT clawbacks | Artificially inflated traffic triggers enterprise refunds and disputes | 1–4% plus reputational cost | Conversion-correlated route analytics |
| Self-inflicted elasticity | Rate rises past willingness-to-pay push senders off SMS entirely | Compounds every other leak | Corridor-level pricing discipline |
The first three are the classic grey-route family, covered in depth in the direct-versus-grey routes guide. The remaining four get less attention, and in 2026 they are where the marginal money is.
Category arbitrage — the quiet leak
Most regulated markets now price transactional and promotional A2P differently, or at least police them differently. Wherever a rate or rule gap exists, some share of promotional traffic will be declared transactional — a loyalty campaign dressed as an account notification, a re-engagement blast shaped like a delivery update. The per-message delta looks small; multiplied across hundreds of millions of messages a year it is a mid-seven-figure line item on a Tier-1 network. The control is content classification at the network boundary: a model that reads the message, not the label the aggregator attached to it, and re-rates traffic that is provably promotional. Operators running classification report that 5–15% of 'transactional' volume is mislabelled on unaudited interconnects.
AIT — the leak that refunds itself out of your revenue
Artificially inflated traffic looks like monetisation success on the month it happens: high volumes, fully billable, healthy corridor yield. Then the enterprise's fraud team correlates the spike against conversion telemetry, disputes the invoice, and the revenue comes back out — often with a discount on future volumes attached as the price of keeping the account. Worse, AIT is the single biggest driver of enterprises capping their SMS budgets or moving verification off SMS altogether. An operator that tolerates AIT on inbound routes is spending long-term A2P demand to buy one quarter of fake volume. The detection and defence playbook is covered in the dedicated AIT piece.
The leak you cause yourself
Termination-rate increases are the fastest monetisation lever and the easiest one to over-pull. The pattern is well documented across corridors that repriced aggressively between 2022 and 2025: an international A2P rate that doubles produces a revenue jump for two to four quarters, then volume erosion as the highest-volume senders — always the OTP-heavy platforms with engineering teams — migrate to flash call, silent network authentication, email fallback, or in-app codes. Within 18–24 months the corridor is earning close to what it earned before, on half the volume, with the displaced traffic permanently gone. Pricing discipline means modelling the elasticity per corridor before the increase: OTP-dominated corridors are elastic; marketing-dominated corridors with regulatory sender-ID lock-in are far less so.
Measure before you fix
Every leak estimate above is a range because the real number is network-specific, and the first project is measurement, not enforcement. The revenue-assurance baseline has three legs: test-call sampling (submit known traffic through the commercial routes that claim to reach your network and observe what actually arrives, on which path, billed at which rate), firewall analytics in mirror mode (classify the live traffic mix without blocking anything), and billing reconciliation (compare SMSC message counts against invoiced A2P volume per interconnect). The three views triangulate. Operators that skip measurement and go straight to blocking tend to burn goodwill on false positives while missing the larger, quieter leaks.
The stack that closes the gap
The operators at the top of the capture curve run the same four-layer stack: a sender-ID registry as the policy anchor, an SMS firewall enforcing it with behavioural models rather than static rules, direct commercial agreements that make the sanctioned path commercially attractive to aggregators, and monthly reporting that ties blocked traffic to recovered revenue so the programme keeps its executive sponsorship. On previously unprotected networks, the first year brings the largest recovery; the follow-on years are where category arbitrage and AIT controls add the next increments.
BroadNet has run A2P monetisation programmes with operators across MENA, Africa, and Asia since 2003 — registry, firewall, and commercial model as one deployment. See the operator solutions overview or start with the SMS firewall.