Wiki 2020 rule pertaining to add on codes with modifier 50 and 51 exempt

[stacyciccone]

What exactly does the new rule from 2020 that states certain add on codes are modifier 50 and 51 exempt mean? Is this a billing rule or a payment rule? If the provider bills a certain add on code that is modifier 50 exempt with the modifier is this considered incorrect billing? Should the bill be denied? Or is it ok for the code to be billed with this modifier but only gets paid 100% of fee schedule/ contract? Or does it still get paid at 1.5% of fee schedule/ contract? If the code is billed on two lines with RT LT does it get paid at 100% first line 50% second line or do both lines get paid at 100% of fee schedule/ contract. We are trying to understand exactly what this new rule means for payment purposes. Also, how does this rule apply to modifier 51? If the code is bill with a modifier 51 should the bill be denied for incorrect billing? If billed with a 51 does it still pay multiple reduction or at 100% of fee schedule/ contract? What are the Medicare rules regarding billing and payment for these exempt add on codes? This would pertain to bills received with a primary code that has a modifier 50 which would pay 1.5% of fee schedule/ contract”

 

[csperoni]

The change means add on codes that may be billed bilateral should be billed twice - once -LT once -RT. For example:
38900-LT (paid at 100%)
38900-RT (paid at 50%)
NOT 38900-50 (paid at 150%)
Add on codes should never require -51.
The change does not affect your reimbursement, only how it gets broken down.
FYI - for the CPT I listed 38900, that is an add on code I bill bilaterally all the time. I didn't even realize the guideline changed in 01/01/2020 until I happened to read another post on this forum months later. We did not have a single carrier (including Medicare) deny 38900-50. From my personal experience, there were some carriers who always wanted -LT, RT not -50. But no one who would pay -50 in 2019 has required -LT, RT.
Also remember that not all codes (whether add on or otherwise), qualify to be billed bilaterally.

Hope that helps!