Is Facebook Ads to Amazon Worth It? Find Out With a Test
By Harry Burman · Updated November 2, 2026
Is Facebook ads to Amazon worth it for your brand? The honest answer depends on the sales your ads cause, not the sales they get credit for. The free Dashboard shows whether a test can answer it, and Starter at $49/mo or Growth at $199/mo runs the holdout.
See profit by channel today, then add holdout tests when you're ready.
Why the usual numbers don't settle it
Meta can't see Amazon checkouts. Amazon Attribution credits tagged clicks with a 14-day, last-touch window, so it misses shoppers who saw an ad and searched later. Neither tells you what you would lose if you stopped.
Sellers on Reddit's r/AmazonFBA and r/FulfillmentByAmazon report mixed results, which is exactly why a test on your own data beats a forum average.
The test that answers it
A geo holdout pauses Meta in some US states and keeps it running in others, then compares Amazon orders. The gap is what your ads add, reported with a range.
What you can decide after the test
Read the range, not a single ROAS figure. If it sits above the sales your margin needs, the ads are earning their keep. If the range covers no lift, you have a reason to cut spend or change the creative and test again.
How Spillmark works
- Upload your reports, or connect. Start with the Seller Central, Amazon Ads, Meta and Shopify reports you already download, or connect with read-only access.
- See profit by channel. Agents show sales minus Amazon fees, product costs and ad spend, with the math behind every number.
- Plan a holdout you approve. Spillmark checks your order history to see whether a geo holdout can answer at your size. If it can, agents plan a test that pauses Meta in a few US states for 4 to 12 weeks and compares Amazon orders by ship-to state. Nothing pauses without your approval, and each test design is locked before it starts.
Pricing
- Dashboard (free): report imports, profit by channel, and a pre-test check.
- Starter ($49/mo): for brands doing $0–$50k a month on Amazon. One holdout test at a time, locked experiment ledger, alerts.
- Growth ($199/mo): for brands doing $50k+ a month. Unlimited holdout tests, branded Amazon PPC tests, scored predictions.
Paid plans start with a 7-day trial for $0. Cancel anytime. Check current prices on spillmark.com.
FAQ
- Will Spillmark change my ads?
- Not on its own. Agents plan tests and show you what to change; nothing changes without your approval.
- Am I too small?
- Maybe, and you'll know before you start. Spillmark shows the smallest change a test could detect at your order volume.
- Is my data shared?
- No. Your numbers are never pooled with other brands or sold.
See profit by channel today, then add holdout tests when you're ready.