Is Q20 a billable ICD-10-CM code?

No. Q20 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does Q20 sit in the tabular list?

Congenital malformations, deformations and chromosomal abnormalities (Q00-QA0), in the block Congenital malformations of the circulatory system (Q20-Q28).

What cannot be coded together with Q20?

Q20 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.

Q20

Q20 — Congenital malformations of cardiac chambers and connections

Non-billable headerICD-10-CM

Q20 is a non-billable header ICD-10-CM code for congenital malformations of cardiac chambers and connections. It cannot be billed on its own: choose one of the more specific child codes below.

Excludes1 — never code together

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

dextrocardia with situs inversus (Q89.3)
mirror-image atrial arrangement with situs inversus (Q89.3)

Other codes that can never be billed with Q20

These codes carry an Excludes1 note pointing at Q20. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading Q20 alone.

Q24.0Dextrocardia
Q89.0Congenital absence and malformations of spleen

Risk adjustment

Q20 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 Q20

9 child codes. Green means billable.

Questions about Q20

Is Q20 a billable ICD-10-CM code?: No. Q20 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does Q20 sit in the tabular list?: Congenital malformations, deformations and chromosomal abnormalities (Q00-QA0), in the block Congenital malformations of the circulatory system (Q20-Q28).
What cannot be coded together with Q20?: Q20 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.