MCMCB Pro
T18.3XXA

T18.3XXAForeign body in small intestine, initial encounter

Billable / specific codeICD-10-CM

T18.3XXA is a billable, specific ICD-10-CM code for foreign body in small intestine, initial encounter. It is valid for submission on a claim.

7th character "A" — initial encounter

The appropriate 7th character is to be added to each code from category T18

A
initial encounter
D
subsequent encounter
S
sequela

Risk adjustment

T18.3XXA 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.

Medicare coverage

T18.3XXA is named in 7 Medicare coverage policies 7 listing it as supporting medical necessity. Which of them applies to you depends on your Medicare contractor, and coverage genuinely differs by state.

  • A56389Billing and Coding: Upper Gastrointestinal Endoscopy and Visualization
  • A56394Billing and Coding: Colonoscopy and Sigmoidoscopy-Diagnostic
  • A56421Billing and Coding: CT of the Abdomen and Pelvis
  • A56456Billing and Coding: Colonoscopy/Sigmoidoscopy/Proctosigmoidoscopy

Related codes at this level

Codes that share T18.3. If T18.3XXA is not quite right, the correct code is usually one of these.

Questions about T18.3XXA

Is T18.3XXA a billable ICD-10-CM code?
Yes. T18.3XXA is a billable, specific ICD-10-CM code and is valid for submission on a claim.
Where does T18.3XXA sit in the tabular list?
Injury, poisoning and certain other consequences of external causes (S00-T88), in the block Effects of foreign body entering through natural orifice (T15-T19).
ICD-10-CMFY2026-Apr· effective April 1, 2026

Loaded directly from the CMS/NCHS ICD-10-CM public-domain release — see data sources and our editorial policy. If this page disagrees with the CMS tabular list, this page is wrong. Reference information for professional coders; not medical or billing advice.