Is W16.21 a billable ICD-10-CM code?

No. W16.21 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does W16.21 sit in the tabular list?

External causes of morbidity (V00-Y99), in the block Slipping, tripping, stumbling and falls (W00-W19).

What cannot be coded together with W16.21?

W16.21 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.

W16.21

W16.21 — Fall in (into) filled bathtub

Non-billable headerICD-10-CM

W16.21 is a non-billable header ICD-10-CM code for fall in (into) filled bathtub. It cannot be billed on its own: choose one of the more specific child codes below. This code also requires a 7th character before it is complete.

This code requires a 7th character

The appropriate 7th character is to be added to each code from category W16

A: initial encounter
D: subsequent encounter
S: sequela

Excludes1 — never code together

These conditions cannot occur together. Billing both on the same encounter is a denial.

fall into empty bathtub (W18.2)

Other codes that can never be billed with W16.21

These codes carry an Excludes1 note pointing at W16.21. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading W16.21 alone.

W18.2Fall in (into) shower or empty bathtub
W18.2XXAFall in (into) shower or empty bathtub, initial encounter
W18.2XXDFall in (into) shower or empty bathtub, subsequent encounter
W18.2XXSFall in (into) shower or empty bathtub, sequela
W65Accidental drowning and submersion while in bath-tub
W65.XXXAAccidental drowning and submersion while in bath-tub, initial encounter
W65.XXXDAccidental drowning and submersion while in bath-tub, subsequent encounter
W65.XXXSAccidental drowning and submersion while in bath-tub, sequela

Risk adjustment

W16.21 does not map to an HCC and does not risk-adjust under CMS-HCC V28. That is normal — most ICD-10 codes do not. It still needs to be coded correctly; it just will not move a RAF score.

Code to one of these instead W16.21

2 child codes. Green means billable.

Related codes at this level

Codes that share W16.2. If W16.21 is not quite right, the correct code is usually one of these.

W16.22Fall in (into) bucket of water

Questions about W16.21

Is W16.21 a billable ICD-10-CM code?: No. W16.21 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does W16.21 sit in the tabular list?: External causes of morbidity (V00-Y99), in the block Slipping, tripping, stumbling and falls (W00-W19).
What cannot be coded together with W16.21?: W16.21 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.