Is I20 a billable ICD-10-CM code?

No. I20 is a non-billable header code. Code to a higher level of specificity using one of its child codes.

Where does I20 sit in the tabular list?

Diseases of the circulatory system (I00-I99), in the block Ischemic heart diseases (I20-I25).

What cannot be coded together with I20?

I20 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.

I20

I20 — Angina pectoris

Non-billable headerICD-10-CM

I20 is a non-billable header ICD-10-CM code for angina pectoris. 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.

angina pectoris with atherosclerotic heart disease of native coronary arteries (I25.1-)
atherosclerosis of coronary artery bypass graft(s) and coronary artery of transplanted heart with angina pectoris (I25.7-)
postinfarction angina (I23.7)

Use additional code

Add a secondary code to capture the detail described below.

code to identify:
exposure to environmental tobacco smoke (Z77.22)
history of tobacco dependence (Z87.891)
occupational exposure to environmental tobacco smoke (Z57.31)
tobacco dependence (F17.-)
tobacco use (Z72.0)

Other codes that can never be billed with I20

These codes carry an Excludes1 note pointing at I20. The conflict binds both ways, but ICD-10-CM only writes it down on one side — so you would not find this by reading I20 alone.

I24Other acute ischemic heart diseases
I25.110Atherosclerotic heart disease of native coronary artery with unstable angina pectoris
I25.111Atherosclerotic heart disease of native coronary artery with angina pectoris with documented spasm
I25.118Atherosclerotic heart disease of native coronary artery with other forms of angina pectoris
I25.119Atherosclerotic heart disease of native coronary artery with unspecified angina pectoris
I25.700Atherosclerosis of coronary artery bypass graft(s), unspecified, with unstable angina pectoris
I25.701Atherosclerosis of coronary artery bypass graft(s), unspecified, with angina pectoris with documented spasm
I25.708Atherosclerosis of coronary artery bypass graft(s), unspecified, with other forms of angina pectoris

Risk adjustment

I20 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 I20

5 child codes. Green means billable.

Questions about I20

Is I20 a billable ICD-10-CM code?: No. I20 is a non-billable header code. Code to a higher level of specificity using one of its child codes.
Where does I20 sit in the tabular list?: Diseases of the circulatory system (I00-I99), in the block Ischemic heart diseases (I20-I25).
What cannot be coded together with I20?: I20 carries an Excludes1 note, which means the conditions it lists can never be coded together with it on the same encounter.