When taxpayers need IRS assistance filing and paying their federal taxes, two of the primary service channels they use are calling telephone lines and seeking in-person assistance at Taxpayer Assistance Centers (TACs). The IRS reports its performance assisting callers on the telephone lines using a metric called Level of Service (LOS), which fails to measure several industry standard factors. TAS has advocated for the IRS to adopt a more comprehensive measure of phone service that includes the quality of the caller’s experience. Although it is commendable that the IRS reported an LOS of 88 percent on its Accounts Management (AM) toll-free phone lines during Filing Season 2024, that calculation includes calls where the IRS routed a caller to an automated response when they wanted to reach a live assistor, calls where the CSR was unable to answer the caller’s questions, and calls where the taxpayer had to call multiple times or was unsatisfied with the service they received from a CSR for other reasons. As such, the LOS is neither a good measurement of service nor an accurate reflection of the taxpayer experience.