Do Amazon FBA sellers pay self-employment tax?

Yes — if you're operating as a sole proprietor or single-member LLC, your net profit from FBA is subject to both income tax and self-employment tax (15.3% on the first $176,100 of net profit in 2026, then 2.9% above that). The S-corp election becomes relevant once your net profit exceeds roughly $80,000–$100,000 annually — above that threshold, structuring salary vs. distributions can save meaningful SE tax.

Do I owe sales tax in every state Amazon operates in?

Probably not directly — Amazon collects and remits sales tax on marketplace sales through Marketplace Facilitator laws in all 45 states with a sales tax. The key exception: if you're selling through your own non-Amazon website, you may have nexus in states where you have FBA inventory stored, and you'd be responsible for collecting/remitting yourself. Check your nexus state list against where Amazon warehouses hold your inventory.

Is FBA inventory a tax deduction?

Yes, but through COGS (cost of goods sold), not as an immediate expense. Under accrual accounting, you deduct the cost of inventory when it sells, not when you buy it. Under cash accounting (available to small businesses under the de minimis inventory rules), you can deduct inventory when paid for, which is simpler but can create mismatches in high-growth years. Most FBA sellers under $10M revenue use cash-method accounting and deduct inventory when purchased.

Are Amazon FBA reimbursements taxable income?

Yes. When Amazon reimburses you for lost or damaged inventory, that payment is taxable income — it's essentially a payment for inventory value you wrote off. The tricky part: if you received the reimbursement in a different year than you deducted the inventory loss, you need to reconcile. Most sellers just report all FBA reimbursements as income on Schedule C and treat them like any other sale.

What business expenses can Amazon FBA sellers deduct?

Common FBA seller deductions: cost of goods sold (inventory purchase price + inbound freight), Amazon referral fees and FBA fees, storage fees, software subscriptions (inventory management, repricing tools, analytics), advertising spend (Sponsored Products, Sponsored Brands), home office if you manage the business from home, business use of phone and internet, professional services (accountant, attorney), shipping supplies if doing prep work, and mileage for business-related travel (sourcing runs, supplier visits).

When should an Amazon seller form an S-corp?

The break-even for S-corp is approximately $80,000–$100,000 of net profit from the business. Below that, the admin cost (separate payroll, additional tax filings, higher accounting fees) typically exceeds the SE tax savings. Above that threshold, paying yourself a reasonable salary (typically 40%–60% of profit) and taking the rest as a distribution can save 15.3% SE tax on the distribution portion. The savings grow as the business grows.

Amazon FBA Seller Taxes: What You Actually Owe (and What You Don't)

Amazon FBA tax is a situation most sellers underestimate. It's not just "report revenue on Schedule C." You're dealing with inventory timing rules, multi-state sales tax exposure, marketplace facilitator law, and reimbursement income that most people miss entirely. Here's the real picture.

How FBA Income Gets Taxed

If you're operating FBA as a sole proprietor or single-member LLC (the default for most sellers starting out), your net FBA profit flows to Schedule C on your personal return. Net profit = gross revenue minus COGS minus all business expenses.

That net profit then hits you with two different taxes:

1. Income tax at your ordinary marginal rate. If your total income (FBA + any wages or other income) puts you in the 22% bracket, your FBA profit gets taxed at 22%.

2. Self-employment tax at 15.3% on the first $176,100 of net self-employment income in 2026, then 2.9% above that. This covers your Social Security and Medicare contributions — as a self-employed person, you pay both the employer and employee halves.

Combined, this often puts the effective marginal rate on FBA net profit at 37%+ for sellers doing meaningful volume.

Inventory and COGS: Where Most Sellers Get This Wrong

Your inventory is not an operating expense — it's an asset that converts to COGS when it sells. The tax treatment depends on your accounting method:

Accrual method: You deduct inventory cost in the year the product sells, regardless of when you paid for it. A large PO in December that sells in January shows up as COGS in January.

Cash method (simpler, available to most sellers under $26 million in annual gross receipts): You deduct inventory in the year you pay for it, regardless of when it sells. Simpler bookkeeping, but can distort profit in high-growth years if you're buying heavy at year-end.

What you should be tracking per unit:

Purchase price
Inbound freight (domestic or international)
Import duties and customs fees
Third-party prep center costs
Inspection fees

All of these roll into your landed cost per unit — which is your actual COGS per unit, not just the invoice price.

Amazon FBA Reimbursements: Yes, These Are Taxable

When Amazon loses or damages your inventory, they issue a reimbursement. Most sellers see this as "getting their money back" and don't report it. This is wrong.

The reimbursement is income. You (presumably) already deducted the cost of that inventory. When Amazon pays you for it, that payment offsets the loss — which means it's taxable compensation, just like a sale.

How to handle it: Report all FBA reimbursements as income on Schedule C. Your accounting software should have a separate category for this so you can see the total at year-end. Amazon's Transaction Reports break out reimbursements by type.

Sales Tax: The Marketplace Facilitator Rules Simplified

This is where most FBA sellers now get relief, not complexity. As of 2026, all 45 states with a sales tax have Marketplace Facilitator (MPF) laws that require Amazon to collect and remit sales tax on your behalf for sales made through Amazon.com.

This means: if you're selling only through Amazon, Amazon handles your sales tax collection and remittance for marketplace sales. You don't need to register in every state or file state sales tax returns for those sales.

What MPF doesn't cover:

Sales through your own Shopify/WooCommerce store
Your own website checkout
Direct invoices to customers

If you're selling through non-Amazon channels, you may have sales tax nexus in states where Amazon stores your inventory — and you'd be responsible for those non-Amazon channel sales yourself. If you have your own store with more than $100,000 in sales or 200 transactions in a state in a year, you likely have economic nexus there and should be registering and filing.

For most pure-Amazon sellers: sales tax is handled. For multi-channel sellers: get a nexus analysis done, ideally when you first launch your own storefront.

Quarterly Estimated Taxes

FBA income is self-employment income, which means no withholding. The IRS expects quarterly payments throughout the year:

Q1 (Jan–Mar): due April 15
Q2 (Apr–May): due June 16
Q3 (Jun–Aug): due September 15
Q4 (Sep–Dec): due January 15

A simple rule: set aside 25%–30% of net FBA profit into a separate savings account for taxes each time Amazon deposits funds. Pay the IRS quarterly from that account. If your net margin is 20% and your total revenue is $300,000, your net profit might be around $60,000 — set aside $15,000–$18,000 per year.

The underpayment penalty for missing quarterly estimates runs about 8% (annualized) of the underpayment in 2026. It's not ruinous, but it's avoidable.

The S-Corp Decision

Once your FBA net profit exceeds roughly $80,000–$100,000 annually, you should run the S-corp math.

An S-corp separates your income into:

Salary (subject to employment taxes)
Distributions (not subject to SE tax)

If you're netting $150,000 from FBA and pay yourself a reasonable salary of $70,000, the other $80,000 in distributions skips the 15.3% SE tax — saving roughly $12,000 per year.

The cost: separate payroll (typically $500–$1,500/year for a one-person operation), an S-corp election filing (Form 2553), and more complex accounting. The math usually works out in your favor above $100,000.

What to Deduct

Common legitimate FBA seller deductions that often get missed:

Amazon referral fees and FBA fees: fully deductible — they're a cost of doing business
Storage fees: deductible business expense
Sponsored Products, Sponsored Brands, Display: fully deductible as advertising
Inventory management software (Sellerboard, Jungle Scout, Helium 10, etc.): deductible subscription
Repricing tools: deductible subscription
Home office: if you use a dedicated space exclusively for your FBA business, calculate the deduction (either actual expenses or simplified $5/sq ft method)
Phone and internet: the business-use percentage is deductible
Mileage: sourcing runs, post office trips, supplier visits — all at the 2026 standard rate (67 cents per mile)
Section 179 for equipment: cameras for product photography, computers, packaging equipment all qualify

The Model Before You Scale

Before placing a large inventory reorder, run the Amazon Seller unit economics model on Reise — it walks through the fee stack, ACoS ceiling, ROAS break-even, and your real margin before the order goes in. Knowing your after-tax take per unit before you buy avoids the situation where revenue grows and take-home doesn't.

The tax layer is the last part most sellers think about. The ones who do well long-term think about it from year one.