Sponsorship thank you letter generator for newsletters
Updated November 10, 2026 · by Book a Sponsor
A sponsorship thank you letter goes to the brand a day or two after its ad runs. Thank them, give the ad's numbers, and offer the next date with a price. Brands do come back: of 13,766 brand and newsletter pairs we could follow for 30 days, 22.4% had a second ad we could see in that same newsletter within 30 days.
example below: 12,000 subscribers, 5,400 opens, 260 clicks, a sponsor called Acme · change it above · what you type goes in the page address, with no account
Subject: Thank you for sponsoring Your Newsletter: how the November 4 ad did
Thank you letter · to Acme · November 2026
Hi Sam,
Thank you for sponsoring Your Newsletter on November 4. Here is how Acme's ad did:
5,400 of the 12,000 subscribers opened the issue (45.0%).
260 of them clicked your link, 4.8% of the people who opened.
Two readers replied to ask where to buy it.
If you want to run again, the next open main slot is December 2 at $400, or four issues for $1,200 (25% off per issue). Should I hold it for you?
Thanks again, Alex Your Newsletter
When they book, before the ad runs
Hi Sam, thank you for booking Your Newsletter for November 4. To get it right, send the ad copy (up to 150 words), the link and one image by [two business days before]. I will send the numbers the day after it runs.
The rebook price is a modelled middle price for a 12,000-subscriber newsletter in this niche, fitted to 377 newsletters' printed main-slot prices, read November 4, 2026 (middle half $250 to $725). The four-issue price is 25% off per issue, the median on 58 newsletters' rate cards read November 4, 2026.
Cite this: Of 13,766 brand and newsletter pairs whose first ad Book a Sponsor saw 30 or more days earlier, 22.4% ran in the same newsletter again within 30 days; within 60 days, 26.8% of 7,707. Counted November 7, 2026. A floor: we do not read every issue of every newsletter. Source: Book a Sponsor, https://bookasponsor.com/sponsorship-thank-you-letter
How often a newsletter sponsor comes back
We followed each brand in each newsletter from the first ad we saw. A pair counts only once we could watch it for the whole window, so the 30-day row uses first ads from at least 30 days before November 7, 2026.
Brand and newsletter pairs
Pairs
Matching pairs
Share
A second ad in the same newsletter within 30 days
13,766
3,088
22.4%
A second ad in the same newsletter within 60 days
7,707
2,065
26.8%
Three or more ads in the same newsletter, first ad 60+ days back
7,707
1,237
16.1%
Of the 2,065 second ads within 60 days, half came within 8 days of the first, and the middle half between 5 and 26 days. A gap that short can be a run of issues booked at once, so not every second ad is a choice made after the first one ran. We cannot tell which of these followed a thank you letter.
counted November 7, 2026 · ads read in published newsletter issues · newsletters only, not podcasts or YouTube
How to write a thank you letter to a sponsor
Send it a day or two after the ad runs, when the clicks are in. Open with the thanks and the date, so the brand knows which ad you mean. Then the numbers: how many people opened the issue and how many clicked their link. Raw counts beat a percentage alone, because the brand will compare them with what it paid. If a reader replied or a sign-up came through, add one line about it. Then make the next booking easy: name the next open date with its price, and end on a question they can answer with a yes.
When the brand books the first time, send a shorter note: thanks, the date, and when you need the copy, the link and the image. The letter above has both. To get the price right, use the sponsorship calculator or the package builder; to bill the next run, the invoice template.
Where the numbers come from
The rebook shares come from Book a Sponsor's sponsor data: ads read in published newsletter issues, the same rows behind the newsletter sponsors list, counted November 7, 2026. A brand is grouped by its web domain. A second ad counts when it is in a different issue on a later day. We started reading many more issues in late August 2026, and we do not read every issue of every newsletter, so a brand can come back without our seeing it: treat each share as a floor. The rebook price is a modelled middle price for a newsletter your size, fitted to the main-slot prices of 377 newsletters that print a price and a list size, read November 4, 2026.
Need the first sponsor? Find the brands that already buy
free run · about a minute
Questions
What should a sponsorship thank you letter include?
Four things: thank you for the date the ad ran, the ad's numbers (opens, clicks, and anything a reader said), the next open date with a price, and one question, such as "Should I hold it for you?". Keep it short enough to read on a phone.
When should I send a thank you letter to a sponsor?
A day or two after the ad runs, once the clicks are in. Of the brand and newsletter pairs that ran again within 60 days, half did so within 8 days of the first ad, so the ask is best made while the first one is fresh.
Should I ask the sponsor to book again in the thank you letter?
Yes, in one line with a date and a price. 26.8% of the brand and newsletter pairs we could follow for 60 days had a second ad in that time, so asking is reasonable. The four-issue price gives them a reason to book more than one.
What if the ad did badly?
Send the numbers anyway, and say what you would change, such as a shorter ad or a clearer link. The brand sees its own clicks either way, and a report with a plan gives it a reason to try again.
Does this work for an event or nonprofit sponsor?
The parts are the same: thank them, say what their money did in numbers (attendees, people reached, meals served), and name the next thing they can sponsor. Change the wording above to fit. The rebook numbers on this page are about newsletter ads only.
Is anything I type stored?
Your entries travel in the page address and the letter is built from them. We don't ask for an account, and ordinary web server logs can record a page address, so leave out anything private.
Sources
Rebook shares: Book a Sponsor's sponsor data, 18,168 brand and newsletter pairs with a dated ad, counted November 7, 2026 as described above.
Four-issue discount: newsletters' own rate cards, read November 4, 2026, as on the package builder.
Fill the next slot with a brand that already buys
Paste your newsletter. Book a Sponsor lists the brands that sponsored newsletters like yours, finds the person who buys the ads, and emails them every day from its own mailboxes. You get the replies and close the deal.
$1 card check gets 200 emails, then a plan from $19/mo · first sponsor reply inside 30 days or your money back