---
title: "Self-employment (SE) tax on Schedule C net profit — Social Security to the 2026 $184,500 wage base, Medicare, Additional Medicare, and the deductible half."
method: POST
path: "/v1/tax/self-employment"
tags: ["Payroll & tax"]
---

# Self-employment (SE) tax on Schedule C net profit — Social Security to the 2026 $184,500 wage base, Medicare, Additional Medicare, and the deductible half.

`POST /v1/tax/self-employment`

## Request

- Base URL: `` (relative, and it does not resolve against the document’s source URL)
- URL: `/v1/tax/self-employment`
- Auth: none declared

Self-employment (SE) tax on Schedule C net profit — Social Security to the 2026 $184,500 wage base, Medicare, Additional Medicare, and the deductible half.

Payment: x402 ($0.05 USDC on eip155:8453). Call unpaid to receive an HTTP 402 with requirements, then retry with the PAYMENT-SIGNATURE header. Method: seBase = netProfit*0.9235; SS = 12.4%*min(seBase, 184500 - W2 SS wages); Medicare = 2.9%*seBase; +0.9% over the filing threshold; deductible half = (SS+Medicare)/2

## Request body

- object
  - `netProfit` number, required
  - `filingStatus` 'single' | 'mfj' | 'hoh' | 'mfs'
  - `w2SocialSecurityWages` number

## Response `200`

Verified result + provenance (formula, sources, reproducible SHA-256 hash).

## Other responses

- `400`: Invalid input (no charge) — body echoes the JSON Schema.
- `402`: Payment required — PAYMENT-REQUIRED header carries the x402 accepts[] quote.

---

[API](https://skmtc.dev/x402toll/apis/tollbooth-verified-calculators-for-ai-agents.md) · [All operations](https://skmtc.dev/x402toll/apis/tollbooth-verified-calculators-for-ai-agents/llms.txt) · [OpenAPI document](https://skmtc.dev/x402toll/apis/tollbooth-verified-calculators-for-ai-agents/revisions/60cb70a3e1a5?raw)