Question: We have a coder who frequently applies the 51 modifier to nearly all procedure claims. However, our Medicare Administrative Contractor (MAC) has informed us that this modifier will be automatically added when necessary. Is it true that it will be applied automatically, or should we continue to add it? Minnesota Subscriber Answer: You should probably stop using it, depending on which payers you’re billing. “Medicare does not recommend reporting Modifier 51 (Multiple procedures) on your claim,” said the Part B MAC WPS Medicare in its Modifier 51 Fact Sheet. “The processing system has hard-coded logic to append the modifier to the correct procedure code.” Here’s why: When billing for multiple surgical procedures performed on the same date, the payer’s system needs to decide the pricing for each procedure. This is done by ranking them according to the fee schedule amount. The procedure with the highest fee is paid in full, while the remaining procedures conducted on the same day are subject to a 50 percent reduction. If the services that you bill apply to multiple procedure pricing, the system will add the modifier, so it could cause the payer to cut your pay by an additional 50 percent if you also append the modifier to your claims. Worse yet, your question suggests that your coder is applying this modifier even when you’re only billing one surgical procedure. This represents another method by which Medicare contractors have discovered practices are not fully maximizing their reimbursement. The Medicare Quarterly Provider Compliance Newsletter Volume 3, Issue 4 indicated that “When only one surgical procedure is performed and modifier 51 is claimed, the reimbursement is inappropriately reduced by 50 percent … It is inappropriate to use multiple procedure modifiers when there is no second procedure performed.” Therefore, it may benefit your practice to discontinue the use of modifier 51 in general unless your payer instructs you otherwise. If so, get the insurer’s guidance in writing to ensure that you use the modifier correctly and continue to collect appropriate reimbursement. However, in that scenario, if you document a separately identifiable evaluation and management (E/M) service, append modifier 25 (Significant, separately identifiable evaluation and management service by the same physician on the same say of the procedure or other service) or 57 (Decision for surgery) to the E/M code, but leave the procedure unmodified. Lindsey Bush, BA, MA, CPC, Development Editor, AAPC