Type of bill (TOB)

The code has four characters, but Medicare reads three. The leading zero is ignored. The second digit names the type of facility, the third classifies the type of care (clinics and special facilities have classifications of their own), and the fourth is the frequency code, which says where this bill sits in the episode of care. So 032x is a home health claim under a plan of care, 021x is a skilled nursing facility inpatient claim, and 018x is a hospital swing bed claim. The values come from the National Uniform Billing Committee’s Official UB-04 Data Specifications Manual, and Medicare contractors make the codes for Medicare claims available.

The frequency digit does most of the daily work. In Medicare home health, the period claim has to end in 9, a final claim that follows a notice of admission; 7 replaces a prior claim, 8 voids one, and the notice of admission itself is 032A. Late charge bills ending in 5 are not accepted on these claims, so a service missing from a paid period goes back on an adjustment. Type 034x carries what the period payment does not: services for a patient with no home health plan of care, and, even during an open period, items such as osteoporosis drugs and certain vaccines.

The mistake is sending a corrected claim with the original frequency code. A rebill for the same dates should carry the replacement or void code the payer expects, along with whatever reference to the original claim that payer’s corrected claim rules call for. Check the type of bill before any rebill goes out, and check that the facility digit matches the provider’s enrollment.