Purpose
Determine whether a given vendor payment is 1099-reportable and, if so, the exact form and box number it belongs in — using the vendor's W-9 entity classification, the nature of the payment, and IRS thresholds. Eliminates the guesswork and inconsistency that lead to misfiled or omitted information returns and B-notices.
When to Use
Invoke this skill when the user asks to:
- Determine if a specific vendor or payment is 1099-reportable
- Decide whether a payment goes on Form 1099-NEC or 1099-MISC
- Identify the correct box number for a reportable payment
- Resolve whether an LLC, corporation, or attorney requires a 1099
- Clean up or validate a vendor master file ahead of year-end reporting
- Interpret a W-9 to classify a vendor for information reporting
Inputs Required
Before starting, collect:
- Vendor legal/entity type: From W-9 — Individual/sole proprietor, Single-member LLC, LLC (C/S/P election), C-Corp, S-Corp, Partnership, Trust/Estate, or Tax-exempt
- Federal tax classification checkbox: The exact box marked on the W-9 (e.g., "Individual/sole proprietor," "C Corporation," "Limited liability company" with tax classification letter)
- Payment category: Nature of the payment — services, rent, legal fees, medical/healthcare, royalties, prizes/awards, interest, dividends, etc.
- Annual payment total: Aggregate paid to the vendor in the calendar year
- Payment method: Check/ACH/wire vs. credit card or third-party network (affects reportability)
- Backup withholding status: Whether the vendor is subject to backup withholding or failed TIN matching
- Tax year: The reporting year (rules and box numbers can shift year to year)
If payment method is not provided, assume check/ACH (reportable). If tax year is not provided, apply the most recent IRS rules and note the assumption.
Instructions
Step 1: Apply the Corporation Exemption Screen
Determine if the entity type exempts the vendor from most reporting.
- C-Corp or S-Corp (W-9 box marked "C Corporation" or "S Corporation," or LLC with C/S election): Generally exempt from 1099-NEC and most 1099-MISC boxes.
- Critical exceptions that override the corporation exemption (report even for corporations):
- Attorney/legal fees → always reportable
- Gross proceeds paid to an attorney → always reportable
- Medical and healthcare payments → reportable even to corporations
- Substitute payments, fish purchases for cash, federal executive agency payments
- Individuals, sole proprietors, single-member LLCs (disregarded), partnerships, LLCs taxed as partnership, trusts/estates: Do not get the exemption — proceed to full classification.
State clearly whether the exemption applies or is overridden, and why.
Step 2: Apply the Payment-Method Screen
- If paid by credit card, debit card, or third-party network (PayPal, etc.): Not reportable by the payer — the payment settlement entity reports on 1099-K. Stop and flag as non-reportable via this method.
- If paid by check, ACH, wire, or cash: Continue to threshold and category screens.
Step 3: Apply the Dollar Threshold
Check the annual aggregate against the threshold for the payment type:
- Nonemployee compensation / services (1099-NEC Box 1): $600
- Rents (1099-MISC Box 1): $600
- Other income / prizes / awards (1099-MISC Box 3): $600
- Medical & healthcare (1099-MISC Box 6): $600
- Gross proceeds to attorney (1099-MISC Box 10): $600
- Royalties (1099-MISC Box 2): $10
- Interest / dividends: $10 (routes to 1099-INT / 1099-DIV, not NEC/MISC)
- If under threshold: not required, but note backup-withholding cases below still trigger reporting.
Step 4: Route to the Correct Form and Box
Map the payment category to form and box:
Form 1099-NEC
- Box 1 — Nonemployee compensation: Fees, commissions, contractor/services payments, professional service fees paid to non-corporations (and attorney fees for legal services regardless of entity).
- Box 4 — Federal income tax withheld (backup withholding).
Form 1099-MISC
- Box 1 — Rents: Office, equipment, land, machine rentals.
- Box 2 — Royalties.
- Box 3 — Other income: Prizes, awards, other taxable income not covered elsewhere.
- Box 6 — Medical and healthcare payments: Payments to physicians/providers, incl. corporations.
- Box 10 — Gross proceeds paid to an attorney: Settlement proceeds (distinct from attorney fees for services in NEC Box 1).
- Box 4 — Federal income tax withheld.
State the exact form and box, and if a single vendor spans multiple categories, list each mapping separately.
Step 5: Apply Backup Withholding Overlay
- If the vendor is subject to backup withholding (missing/incorrect TIN, IRS B-notice, or failure to certify): report the payment regardless of threshold, and record withheld amounts in the appropriate Box 4.
- Flag any vendor with an unmatched TIN as requiring a W-9 refresh before filing.
Step 6: Deliver the Classification Verdict
Produce a clear determination with the reasoning chain that led to it, plus any data gaps that must be resolved before filing.
Output Format
- Structure: A determination summary line, followed by the reasoning walkthrough by screen, then a compact result table
- Length: 350–600 words
- Format: Prose reasoning + one summary table
- Sections: Determination Verdict → Reasoning by Screen (exemption, method, threshold, routing, backup withholding) → Result Table (Form / Box / Amount / Reportable Y-N) → Action Flags
- Tone: Precise, compliance-minded, and decisive — cite the IRS rule basis for each conclusion without hedging when the rule is clear; flag genuine ambiguity explicitly
Quality Checklist
Before delivering output, verify:
- [ ] The corporation exemption screen is applied AND checked against all override exceptions (attorney, medical, gross proceeds)
- [ ] The payment-method screen correctly excludes card/third-party network payments as payer-non-reportable
- [ ] The stated dollar threshold matches the payment category ($600 vs $10)
- [ ] The final routing names both the specific form (NEC or MISC) and the exact box number
- [ ] Backup withholding cases override the threshold and are noted
- [ ] Any missing W-9 field or unmatched TIN is flagged as an action item before filing
Notes
- The most common misfile is treating attorney and medical payments as exempt because the vendor is a corporation — these override the exemption and must be reported.
- Distinguish carefully between attorney fees for services (1099-NEC Box 1) and gross proceeds paid to an attorney such as settlement funds (1099-MISC Box 10) — they route differently.
- Single-member LLCs are the frequent classification trap: check whether it is disregarded (report to the owner's TIN) or has elected corporate taxation (potentially exempt).
- When W-9 data is incomplete, do not guess the entity type — flag it and treat the vendor as reportable pending a valid W-9 to avoid under-reporting risk.
How to use this skill
This file is a Claude Code skill in Anthropic's standard format — markdown with YAML frontmatter at the top.
Installing in Claude Code:
~/.claude/skills/<folder-name>/SKILL.md— auto-loads in every session anywhere on your machine (recommended for skills you'll use across multiple projects)<your-project>/.claude/skills/<folder-name>/SKILL.md— auto-loads only when working in that project (recommended for project-specific skills)
Restart Claude Code or open a new session to register.
Using in Claude.ai, ChatGPT, Gemini, or other AI tools:
- Drag this file into a new chat, or copy and paste its contents
- Send your task or request as your next message — the AI will apply the skill where it fits
For Claude Code skill details: https://docs.anthropic.com/en/docs/claude-code/skills