Publishers list their placements once and wake up to bookings, not threads. Sponsors find the right newsletters and book on the spot — guided by Bellwether, our free sponsor-intelligence tool.
Free to list inventory · Free sponsor intel · Commission only
Illustrative data shown. Figures and publisher names are examples, not customer results.
Every category in the flock
Deepest in B2B tech — software, AI, security and startups.
Bellwether Intel100% free
Bellwether watches the newsletters we monitor and shows which sponsors are buying, where they run, and how often they come back. Tools like this cost hundreds a month — Bellwether is 100% free for every member of the marketplace.
Illustrative data shown. Advertiser names and figures are examples, not live data.
What’s keeping you up
One sponsorship a month is a spreadsheet problem. Twenty is an operations problem — and that is where revenue quietly leaks out while you are not looking.
Rates in one tab, the run schedule in another, and the real answer somewhere in your sent folder.
Assets arrive as attachments, revisions arrive as replies, and nobody is sure which file is final.
Without one calendar per placement, the same slot gets promised to two advertisers in the same week.
A booking runs, and chasing the payment depends on someone remembering that it ran at all.
Lose the spreadsheet, not the sleep.
For sponsors — buy newsletter ads
Publishers list what they have — primary slots, classifieds, dedicated sends — with real rates, real specs and a real calendar. Search it, filter to your audience, and book the slot you want. No introductory email, no rate-card request, no waiting on replies.
The Ops Letter
Newsletter48.2k· Next opening 12 Mar
$1,850
per issue
Signal & Noise
Dedicated send31.4k· Next opening 14 Mar
$2,400
per send
Build Notes
Newsletter112.9k· Next opening 21 Mar
$3,100
per issue
For newsletters — sell ad space
Every booking arrives with its creative attached and already checked against the spec you set. Approve it, send it back with a note, or reject it — and keep the whole exchange on the booking instead of buried in your inbox. Advertisers see the same thread, so good creative clears fast — and your inventory is watched even when you are not.
Bookings
1 needs reviewNorthwind Tools
Above the Fold · Issue #184 · 12 Mar
Cobalt Analytics
Mid-roll · 60s · Ep. 92 · 14 Mar
Harbor Payroll
In the Fold · Issue #185 · 19 Mar
Vela Insurance
Above the Fold · Issue #186 · 26 Mar
Creative review
Sponsorship reporting
Booked revenue, fill rate and deal size update as bookings move through the pipeline — so the number you quote at the end of the month is the number the system already has.
Illustrative data shown. Figures and publisher names are examples, not customer results.
Pricing
No subscription. No listing fee. No setup fee. Nothing at all for the sponsor intelligence. The only money that changes hands is a commission on a booking that actually happened — so a quiet month costs you nothing.
The newsletter sponsorship platform
A real calendar per placement — direct buys and multi-issue packs, with sold-but-unscheduled inventory surfaced automatically.
Every ad is reviewed. Publishers approve, edit, or request changes; advertisers respond — a full back-and-forth, tracked.
See which sponsors run where across the newsletters we monitor, how much reach they buy, and who to pitch next. 100% free.
Separate publisher and advertiser dashboards, plus a super-admin view over every account, brand and booking.
Dimensions, copy length and file limits are set per placement, so what an advertiser uploads already fits the slot.
Bookings become invoices without re-keying. Payment status sits on the booking, where everyone can see it.
Newsletters
No subscription, no listing fees — we get paid when ewe get paid.
Advertisers
Sign in and tell us whether you’re a publisher or an advertiser — we’ll set up the right workspace for you. It takes about five minutes.
Join the flock