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MigoSMTP
Marketplaces

Email for two-sided platforms with many senders

Buyers, sellers and your own team all send through one platform. Keep each of them in check.

Email for buyers, sellers and your team, with AI abuse flags and per-seller limits

Marketplace
Seller AOwn identity
own pool
Seller BOwn identity
own pool
Seller COwn identity
own pool
One seller never hurts all
Per-seller
Isolated
Every seller has an identitySellers get their own sending identity and limits, so one bad actor cannot damage the marketplace.
Seller onboarding
Verify business email
Add sending domain
Publish DKIM and SPF
Accept sending policy
Start at low limit
Verified
Staged limits
Verify before they sendNew sellers verify their domain and complete checks before volume limits are lifted.
Order #[id]Seller A · [total]
Contact seller
message.created
Seller notified
FromBuyer
ToSeller A
Order#[id]
ReplyRouted
Reply routed back
Two-sided
Reply routing
Buyer and seller stay in touchOrder and message notifications flow between buyers and sellers, from the marketplace's own address.
OrdersReceipts, shipping
PromotionsSeller campaigns
Marketplace gatewayPer-seller pacing
Always first
Rate limited
Protected lane
Fair share
Transactions beat promotionOrder messages ride a protected lane while seller promotions wait their turn.
Seller health
AI
Seller AFast replies
Healthy
Seller BSome complaints
Coach
Seller CLate replies
Coach
Seller DMany complaints
Review
Coaching first
Fair review
AI scores seller health continuouslyA model blends complaints, bounces and response times into a seller trust signal. Weak ones get a coaching email, risky ones get a hold.
Seller policy
Daily cap for new sellers[n]
Throttle on complaintsAbove [n]%
Pause on abuseAutomatic
Appeal reviewSupport queue
Auto-throttle
Appeal flow
Throttle or pause automaticallyPolicies slow or suspend a seller when thresholds are crossed, without manual work.
Sellers
Verify
Order flow
Lanes
AI trust score
Enforce
Typical marketplace email
New order for sellerReal-time noticePriority
Buyer confirmationAfter purchaseCritical
Message between usersRelayed through the platformStandard
Payout noticeSettlement updatePriority
SMTP relayREST APIWebhooksDedicated IPsDKIM signingInbound parseTemplatesAnalyticsSuppression listsReputation monitoringEmail validationTeam roles and audit logSMTP relayREST APIWebhooksDedicated IPsDKIM signingInbound parseTemplatesAnalyticsSuppression listsReputation monitoringEmail validationTeam roles and audit log
The challenge

What marketplaces struggle with

Problem

User-to-user messages can be abused

How we help

Limits, suppression and abuse controls stop misuse of relayed mail.

Problem

Sellers expect their own branding

How we help

Verified sender domains and templates per workspace.

Problem

Support needs to trace any message

How we help

Searchable logs by recipient, subject or ID.

How a message travels

From your app to the inbox, with checks at every hop

Your appSends by SMTP or API with your key.
IntakeAuthenticates, validates and rate-checks the request.
Queue and routingPrioritises mail and picks the right IP pool.
Signing and deliverySigns with DKIM and delivers with provider-aware pacing.
Inbox and eventsDelivery, bounce and engagement events flow back to you.

Best practices that protect delivery

Use a reply-to relayHide personal addresses and keep conversations on the platform.
Set per-seller limitsPrevent a single seller from affecting shared reputation.
Monitor complaints by sellerAct quickly on outliers.
Overview

Marketplace email with MigoSMTP in short

Use cases

Where teams use it

New order for seller

Notify sellers in real time about new orders, on a priority stream, and use delivery events to alert your team when a seller never receives one.

Buyer confirmations

Confirm purchases to buyers at once, kept apart from user-generated messages so a content problem cannot delay core transaction mail. Delivery events confirm the buyer was informed.

Buyer-seller messaging

Relay conversations through platform addresses so personal emails stay hidden, replies come back by inbound routing, and limits curb unsolicited volume. Abuse reports go to your team.

Payout and settlement notices

Send settlement and payout updates to sellers with an audit-friendly record, and give support a searchable log of what each seller was told. Disputes can be checked quickly.

AI features

AI-assisted marketplace email

Risk flags

Relay content screening

Scan relayed user messages for spam, phishing links or off-platform solicitation and hold suspicious ones. Trust and safety staff review the queue and decide to release or block.

Anomaly

Seller complaint grouping

Group complaints and bounces by seller to show who is driving reputation risk, with a plain-language summary. Your team chooses whether to contact, limit or suspend.

Copilot

Support search copilot

Ask for the email history of an order or user in natural language and get the matching log entries. The tool is read-only and does not resend or edit anything.

Agent-ready

Agent-ready platform API

Approved agents can check seller domain status or message state via an MCP-compatible API, with scoped keys and a human approval step for sensitive actions.

AI features are assistive and advisory, so your trust and safety and support teams review flags and keep control of seller and message decisions. [Confirm which AI features are available at launch.]

Best practices

Best practices for marketplace email

Use a reply-to relay

Route conversations through platform addresses so personal emails stay private and you keep a record of the exchange.

Set per-seller limits

Start new sellers on modest caps and raise them with good history, so a single account cannot damage shared reputation.

Monitor complaints by seller

Break down bounce and complaint rates per seller and act early on outliers, before providers notice the pattern.

Sanitise user-generated content

Strip or rewrite risky links and attachments in relayed messages, and add a clear report-abuse link to every relay.

Verify seller domains

Only allow branded sending after DNS checks pass, and fall back to a platform address for sellers who do not verify.

FAQs

Marketplace email: frequently asked questions

How do I relay messages between buyers and sellers by email?

Generate a unique platform reply-to address per conversation, send each message from your domain and receive replies through inbound routing. The platform forwards the reply to the other party, keeping real addresses private and logging the exchange. Expire addresses when conversations close.

How do I stop users abusing my marketplace's email?

Apply per-user and per-seller rate limits, screen relayed content, suppress addresses that complain, and provide a report-abuse link. Review outliers regularly and escalate repeat offenders according to your platform policy. Publish clear acceptable-use rules so enforcement is consistent and defensible when sellers dispute it.

Can sellers send under their own brand?

Yes, if they verify their own sending domain with SPF and DKIM. Sellers who do not verify can send through a shared platform address with their name in the display. Unverified sellers keep a safe, working fallback sender. [Confirm per-workspace domain support.]

Should marketplace transactional and user messages share a stream?

No. Keep order and payout notices on a protected stream and relayed user messages on another. Content written by users carries more risk, and separation stops an abuse issue from delaying core transaction mail. Treat each stream as a separate reputation.

How does support trace a missing email?

Search the message log by recipient, subject or message ID to see accepted, deferred, bounced or delivered status with timestamps. Webhooks can also surface status inside your own support tools. Keep message IDs in your own order records so support can link them quickly. [Confirm log retention period.]

How do I protect platform reputation when sellers misbehave?

Use per-seller limits, suppress complaining recipients quickly, and track complaint rates by seller. Isolate high-volume or risky sellers on a separate pool if needed, and keep clear policies for warnings and suspension. Document the warning and suspension steps so decisions are consistent.

Can AI detect spam in relayed messages?

AI can score relayed messages for spam, phishing and solicitation patterns and hold suspicious ones for review. It does not decide alone: your trust and safety team approves release or blocking. Reviewers see why each message was held. [Confirm which AI features are available at launch.]

How can AI help marketplace support teams?

A copilot can find and summarise the email history for an order or user from the logs in plain language. It is read-only, and staff decide any action. Results link back to log entries. [Confirm which AI features are available at launch.]

Customer story

[Add a customer quote or result from a marketplace customer]

[Name, title, company]

Ready to see it with your sending?

Tell us about your volume and setup and we will walk you through the right configuration.

Start sending in minutes.

Create an account, add your domain and send your first email.