Compliance with STIR/SHAKEN is uneven across the telecom industry, according to a new report from TNS. Wireless and wireline traffic to smaller top communications service providers (CSPs) shows elevated percentages of robocalls compared with larger CSPs, and TNS data shows bad actors are exploiting gaps in the telecom ecosystem where STIR/SHAKEN isn’t fully deployed. STIR/SHAKEN is the framework adopted under TRACED Act — and phased in from 2021–2024 — designed to deter unwanted robocalls.

While STIR/SHAKEN can confirm that a call is signed, it is unable to determine every dimension of call intent, reputation or legitimacy, TNS noted.

“Though STIR/SHAKEN has come of age, AI-enabled fraudsters keep raising the bar,” according to the report about providers and robocalls. “Compliance data for the first half of 2026 reveals incremental progress at the industry’s highest echelons alongside persistent trust challenges for the non-top-tier.”

More specifically, the research found that:

• Seven of the top CSPs, which have stabilized about 85% of inter-carrier traffic, tend to have a compliance grade of A. However, TNS cautions, A grade does not equal trust.
• Smaller providers, which have about one-fifth of signed traffic that terminates to their network, remain exposed to bad actors employing robocalls. According to TNS, much of the exposure is due to TDM/SS7 hops that strip STIR/SHAKEN signatures, combined with limited direct SIP peering to top-tier CSPs.
• Fraudsters continue to become more sophisticated. They are using artificial intelligence and VOIP — as well as multimodal campaigns that combine voice and text — to pressure victims into clicking, calling back, or making payments. They are also are harvesting target lists and prioritizing victims.

“The industry must now close the gaps through modernization and layered defenses to continue to restore trust in voice communications,” TNS said in the report about providers and robocalls.