How to auto-reply to Facebook Marketplace messages with AI
A practical guide to setting up AI auto-replies for your Facebook Marketplace inbox so no buyer goes unanswered — even while you sleep.
Facebook Marketplace rewards speed. The seller who answers "Is this still available?" first usually gets the sale — and on a busy listing that question can land dozens of times a day. Answering every one by hand doesn't scale.
This guide walks through how AI auto-replies work and how to switch them on for your own inbox.
Why response time decides the sale
Most Marketplace buyers message several sellers at once. Whoever replies first gets to set the terms: the viewing time, the price anchor, the next step. A reply that lands in three seconds feels like a real, attentive seller. A reply that lands three hours later usually finds the buyer already talking to someone else.
Sellers who reply within five minutes are far more likely to close than those who reply within an hour. The first message is the whole game.
How AI auto-reply works
The flow is simple:
- The extension watches your Marketplace inbox for unread conversations.
- When a new message arrives, it sends the conversation to the AI backend.
- The AI drafts a reply in the buyer's language and tone, then sends it back.
You stay in control of the prompt — the AI's instructions — so every reply sounds like you, not a robot.
Setting it up
Getting started takes a couple of minutes:
- Install the Chrome extension and log into Facebook as you normally would.
- Write a short prompt describing your tone, your listings, and any rules ("never quote below asking price").
- Connect your account and click Start.
That's it. The AI reads new leads and replies automatically while you focus on closing deals.
What to put in your prompt
A good prompt is specific. Tell the AI:
- Who you are — "You're a salesperson at City Auto Sales."
- What to do — confirm availability, offer a viewing, answer common questions.
- What not to do — don't agree to big discounts, don't share your address until a time is booked.
Keep a human in the loop
Auto-reply doesn't mean hands-off. Check your inbox once or twice a day, jump into the conversations that matter, and let the AI handle the repetitive first replies. The result: every buyer hears back instantly, and you spend your time on the ones ready to buy.
Ready to try it? You get 200 replies free — no card required.
Try it free on your inbox
Install the extension and let the AI reply to your next Marketplace buyer — 200 replies free.