Newsletter sponsorship platform connecting brands with publishers
Stage
Not given
Not given
Founded
Not given
Not given
Based in
US
Not given
Pricing model
Paid
Freemium
Pricing
$300 USD per month, billed monthly. Includes unlimited flows, campaigns and segments, 50,000 emails per month (more available on request), MCP server for any agent client, consent and unsubscribe handling, and DNS setup. Cancel anytime from billing portal.
Free to join for both brands and newsletters. Brands pay the sponsorship price only after a newsletter accepts. LetterBid keeps 25% of each sponsorship as fee (includes payment processing); newsletters receive 75%.
Key features
REST API for event-driven emails with idempotency keys
Automatic email deduplication
One-click unsubscribe and automatic consent enforcement
Campaign dry runs before sending
Full analytics on opens, clicks, unsubscribes and conversions
Domain verification with live DNS record checking
Newsletter discovery with verified audience data
Three sponsorship placement types: dedicated email, sponsored ad, banner ad
Direct, multi-newsletter, and recurring campaign types
Custom offer negotiation with up to 3 counter offers
Payment held in escrow until delivery approval
Verified newsletter badges with audience verification
Delivery reports and brand approval process
Public storefront for newsletters with shareable booking link
Stripe integration for payouts on the 15th of each month
Dispute resolution with LetterBid team intervention
What makes it different
AI agents design and manage email flows in plain language over MCP
Automatic timezone-aware daytime delivery
Built-in compliance with bounce/complaint monitoring and auto-pause
Transparent, fixed pricing with no hidden fees or surprise charges
Payment held in escrow and released only after delivery proof and brand approval
Verified audience data for newsletters to reduce guesswork
No upfront payment required; brands pay only after newsletter acceptance
Dispute resolution system with fair split option if sides cannot agree
Ringmaster
LetterBid