How we keep deliverability high

What we do to make sure your emails land


Everything we do comes down to three things:

  1. Make sure the only people getting your newsletter are the ones who actually want to get your newsletter.
  2. Make sure the emails being sent out are content-rich, accessible, and performant.
  3. Be deliberate and careful in who we allow onto the platform to make sure our reputation stays golden.

There's no secret sauce — it's not rocket science. It's just diligence and good engineering. But for the details, keep reading!

Mandatory double opt-in

Some email platforms treat double opt-in as a "table stakes" feature that authors can turn on and off as they wish, or even treat cold emailing (the practice of sending emails in bulk to addresses who haven't given you permission to do so) as legitimate.

Buttondown... does not. Every single subscriber on Buttondown must explicitly opt into your newsletter. This keeps the risk of spam complaints low, your engagement high, and readers everywhere happy.

That being said, we're nothing if not flexible and hospitable to other use cases. If you're confirming double opt-in outside of Buttondown (for instance, asking authors to confirm their interest as part of a registration or checkout flow) you can always email us and we can discuss other options!

Automatic clean-up

Even if a subscriber to your newsletter is a real human who explicitly signed up to hear more from you, you might not want to keep them around if they haven't opened a single email from you in months. This is referred to as a number of different things across the industry ("list cleaning", "email scrubbing", "email hygiene"...) — we call it subscriber cleanup. It's an automatic opt-in process that checks for folks who are suspected to have abandoned their email address or have never engaged with your content. Removing these folks from your list might feel a bit like ripping off a band-aid (it can be sad to see the big subscriber count go down!) but is great for the long-term health of your subscriber base, because it means your engagement rate amongst your true fans will be higher.

(You can read more about subscriber clean-up here!)

A human eye

Last but not least, every single new Buttondown newsletter who imports subscribers from an external source goes through a manual approval process to make sure everything looks kosher. This is old-school, we know, but it's for the safety of you and every other author on the platform. We take our sending reputation and deliverability seriously, and this helps us maintain our best-in-class benchmarks on both fronts.

(If you're worried that this process is Kafka-esque and will take days on end, worry not — we generally complete it in less than eight hours during the week and less than 24 hours during the weekend.)

Offboarding people who don't pass our bar

A human eye is great, but it's not perfect, and circumstances can change — maybe an author starts abusing their API privileges or decides to otherwise violate Buttondown's terms of service by sending emails to folks who haven't signed up for them.

If you're found to have breached our internal threshold for either the number of emails you send that bounce or the number of emails you send that are marked as spam, we'll reach out to talk about your sending strategy. If those conversations don't go anywhere, you'll be removed from the platform.

(Sometimes, when we mention this, we're greeted with a bit of shock and dismay — "so you'll remove me just for sending more emails than usual?!" Buttondown's never off-boarded a well-meaning customer who made a mistake double-sending an email or accidentally imported bad subscribers; it's only ever been malicious actors.)

Pre-flight checks

Before sending your email, Buttondown runs a battery of 62 pre-flight verifications to make sure everything's in ship-shape. We check everything you can think of, like:

  1. Do you have specific words or phrases that Gmail or other inboxes will flag as spammy?
  2. Are any of your images too large?
  3. Did you use the word "attached" without actually attaching a file?
  4. Did you add too many images, meaning that some clients will refuse to load or send your email?

This validation suite makes sure you're sending out the best possible email, and the best possible email gets delivered at the best possible rate.

IP-based subscriber filtering

Buttondown works very hard to make sure all of the subscribers joining your newsletter are legitimate, so that they're not giving your publication a bad reputation. One of the first and most effective lines of defense is checking incoming subscriptions' IP addresses against a combination of both our internal datasets and those of trusted vendors like Spamhaus and Project Honeypot. (Note that we do this by pulling in omnibus data from external sources, rather than polling them, so as to protect the privacy of you and your subscribers.) This lets us immediately filter out automated or malicious bots subscribing to your newsletter.

No in-app cross-promo

One of the bigger product decisions Buttondown has made is to not push cross-promotion — this is the fancy industry term for "when someone subscribes to your newsletter, we suggest three similar newsletters for them to also subscribe to."

There are a number of reasons we do this — mostly, we don't think it's our place to get in between you and your audience — but the biggest one is it hurts everyone's deliverability. Studies that Buttondown's run show that subscribers who sign up for other newsletters through cross-promotion end up reporting emails as spam and unsubscribing at a much higher rate — even for the newsletter that they originally signed up for!

Other platforms taut growth through cross-promotion to juice your subscriber base; while you're of course free to run your own manual promotional efforts, it's not worth the risk to deliverability for us to push them on your behalf.


You don't really need to know what these clumsy-sounding acronyms are, but they're protocols that we (along with many other reputable senders) use to ensure that the emails we send are coming from us, not someone pretending to be us.

Setting up SPF and DKIM are a bit of a hassle to handle yourself, but if you're sending from Buttondown it's automatically handled for you (even if you're sending from a custom domain!) And starting in 2024, Google requires all senders to send their emails with these authentication protocols in place.

We keep it easy for subscribers to unsubscribe

I'm sure this has happened to you:

  1. You bought something online.
  2. You started getting an email every. single. day. from the retailer.
  3. You finally got fed up and hit unsubscribe, except that page took you to another page which took you to another page.
  4. And then you still got an email the next day, because you unsubscribed from "weekly recommendations" but not "hot deals" or whatever.

Yeah — that drives us crazy too. Every email coming from Buttondown is one-click unsubscribe compliant, meaning that there's no labyrinthine set of hoops to jump through to unsubscribe. You might not love this as an author, but it's good for you in the long run — unhappy subscribers turn into frustrated subscribers, frustrated subscribers report your newsletter as spammy, and spam reports tank deliverability.

Emphasis on text over images

Buttondown's default email templates are very plain-text forward. This is nice for aesthetic reasons, but also is very positive on deliverability. Text-heavy, less rococo emails (as compared to their image-heavy counterparts) work great on inboxes of all sizes and shapes and score extremely well in content scanning, meaning that you'll be reaching more of your subscribers more reliably.

Bring your own domain

Last but not least, Buttondown lets you send from own domain (if you own one!) This improves the overall engagement rate for your emails, as they appear more personal and have a higher domain reputation. More importantly, that domain reputation carries with you — even if you leave Buttondown for another service, so long as that service also allows you to send from a custom domain.

What customers say about Buttondown

I made the transition from MailerLite and I have no regrets. I also like that Buttondown focuses on the essentials by design and keeps me grounded and centered on what really matters.
Arthur Cendrier
Author, Thoughtful Inquiry
Overall, Buttondown has been terrific to work with and I recommend them for anybody who's thinking of starting a newsletter or moving over like I did.
Andy Magnusson
Customer Engineering Leader
Wanna know how good Buttondown as a product experience is? I upgraded to Basic before sending the first email, and then upgraded again two days later.
Zak El Fassi
Founder, Zaigood Labs
Mailchimp lost me due to their inferior product and the nightmarish merry-go-around experience with their overseas support team. Buttondown won me over with their superior product and second to none customer service.
Sav Tripodi
CEO, Sanico Software
Your support is amazing and I deeply appreciate how available and helpful you are. I LOVE being able to turn tracking pixels off. I didn't even realize this was an option when I signed up and am SO HAPPY to not track people.
Andrea Mignolo
Method & Matter
I'm also impressed with how responsive you are, and how you directly answer customers. Makes it really clear that signing up for your service was a good decision.
Nicole Tietz-Sokolskaya
Software engineer and writer
Very happy with Buttondown, works smoothly, it's very configurable and I love the minimalist design of the UI. It makes me focus on my writing. Plus, I'm super happy to support independent software and I should mention - the support I receive whenever I have a question is warm and quick :)
Martina Pugliese
Data scientist and storyteller
I just tested the RSS to Email feature for one of my blogs and it was incredibly easy to set up. It took me about 30 mins to figure out the same feature in Mailchimp.
Nicolas Bernadowitsch
This long weekend I fulfilled a long-standing promise to myself to switch my RSS-to-email provider from Mailchimp to Buttondown, and it’s been such a great experience. It’s cheaper, more flexible, less cluttered, and it’s run by Justin Duke who is just delightful and answered a bunch of my questions over the weekend (even though I asked him to please not!).
Rian van der Merwe
Director of Product at PagerDuty
I've been wrangling half a dozen tools to get my stuff up and running recently, almost all of which had some hiccup. Buttondown had zero. It did everything I expected and needed the first time.
Catherine Cusick
Self-Employed FAQ
I, like almost everyone else I've seen talk about Buttondown, am IMMENSELY happy and impressed with your customer service. It turns out we can have nice things, which is really refreshing.
Ed Yong
Staff writer, The Atlantic
Email makes the world go ‘round, and Buttondown is how I manage it all for my keyboard projects.
Tim van Damme
Founder, MVKB
It's a truth, that should be more universally acknowledged, that Buttondown is the best newsletter software. Simple, does exactly what it sets out to do, and reasonably priced.
Noel Welsh
Founder, Inner Product
Buttondown is the perfect fit for my headless newsletter use case. And I contacted support with some specific requests and Justin responded within 30 minutes with great answers and a nice pinch of charm.
Sam Roberts
Software engineer, Tamr
Hands down the easiest way to run a newsletter - and the free version is generous!
Javeed Khatree
SEO expert
With API and Markdown support, you can build workflows that make it so easy to write.
Westley Winks
Peace Corps
I’ve never enjoyed writing newsletters as much as I do with Buttondown.
Kevin Lewis
You Got This!
Buttondown remains the easiest thing I use regularly, and I am grateful for that.
It's a humble app doing a common job but with end users in mind.
Si Jobling
Engineering Manager
Buttondown has been an amazing experience for me. The service is constantly being improved and customer service is the best. My newsletter with Buttondown has grown from a fairly small list to over 15,000 subscribers, and it hasn't broken a sweat yet.
Cassidy Williams
CTO, Contenda
I switched over to Buttondown from Mailchimp because of the difficulty I had with Mailchimp's campaigns, so Buttondown's easy and user-friendly system has been a genuine breath of fresh air.
Jessi Eoin
Illustrator + Comic Artist
You’ve truly built a great product that I feel good about using (vs a monopoly from our tech overlords).
2030 Camp
I love how personal Buttondown feels, especially compared to Mailchimp, Convertkit, and services like that.
Simen Strøm Braaten
This product has been exactly what I’ve needed!
Nathan Bird
Podcast host, Chattanooga Civics
It's already so refreshing compared to the mega companies.
Casey Watts
Author, Debugging Your Brain
Definitely will be using for the foreseeable future. It’s a great service and I feel well cared for. Thank you!
Phoebe Sinclair
I’m a sucker for elegant UI and I really love your site, but above that I think your product has so much value for so many different people. I’m not a coder, I’m only familiar with the bare basics, but I was able to figure out and utilise Buttondown quickly.
Claudia Nathan
Founder, The Repository
The killer feature for me: Buttondown will take an RSS feed then automatically slurp up the content (in their words) and then send it to our subscribers. Job done. They seem like a good company too, so I’d say this is a winner.
Andy Bell
Founder, Set Studio
As a recent user of Buttondown, they are super on the ball. A week ago I discovered a security vulnerability and reported it on Friday afternoon. They acknowledged and fixed it in under two hours. On a Friday night! Talk about going above and beyond for your users!
Predrag Gruevski
Principal Engineer, Kensho
Well may I just say your support experience is already approximately 1 billion times better than ConvertKit. Excited to be switching!
Michael J. Metts
Author, Writing is Designing
Privacy focused sending and sign up form; lets me focus on writing - editor is "just" markdown; simple, elegant design template looks like a blog post; the founder is amazing - he's helped with every question I've had, even outside of Buttondown.
Joe Masilotti
Founder, RailsDevs
We need more nice and professional services like yours on the web.
Tobias Horvath
Designer and developer
No one is paying me to say this, but I love @buttondown so far for my lil newsletter. It’s so smart, simple, and attractive (and to my knowledge, not actively anti-trans!). Customer service is also legitimately excellent.
Julie Kliegman
Copy chief, Sports Illustrated
I love it! It lets me breathe, not compete as I write with other writers.
Devin Kate Pope
Writer and editor
It’s a pleasure working with you. Thank you! (And what a contrast with Mailchimp, where I spent two weeks and a dozen of emails trying find out why our form goes down sometimes (only sometimes), and never really got a real answer.)
Anton Sotkov
Software Engineer, IA
Buttondown exemplifies how I wish most software worked, and I hope to achieve a similar thing with the software I develop in the future.
Matt Favero
Software engineer
It feels incomparably good to be able to email just like a guy named Justin when you have a @buttondown question 15 minutes before you’re about to blast a Geistlist email. (Not a guarantee but wow this guy is human-level good.)
Jacob Ford
Designer About Town
Enter Buttondown, Justin Duke’s lovely little newsletter tool. It’s small, elegant, and integrates well. And it is also eminently affordable.
Will Buckingham
Your settings page is a joy to use and everything about Buttondown makes me happy.
Gareth Jelley
Magazine editor
have been on Buttondown for ~18 months and I can't recommend it enough.
Elizabeth Minkel
Podcast host
You really do make ALL other customer service look terrible by comparison.
Chris Mead
Improv teacher
There is a caring person on the other side of this software, which is one of the things I like the most about Buttondown.
Keith Calder
Film & TV Producer
I’d also like to add that @buttondown is an absolute joy to use. Hats off, Justin!
Elliot Jay Stocks
Creative Director, Google Fonts
Shoutout to @buttondown and @jmduke for building an amazing bootstrapped product for newsletters, all while being very open to feedback and connecting directly with customers 🙏 Easily one of the most enjoyable product experiences I've had.
Den Delimarsky
Head of Ecosystem, Netlify
if you are looking for "newsletter tool for hackers" i tentatively believe the answer is @buttondown full api, compose in markdown, good docs for setting up domain auth, simple subscribe form HTML that you style yourself (or not)
Brian David Hall
Author, Your Website Sucks
I really like @buttondown as a blogging platform, it has the simplicity of Substack but the corporate culture is less toxic.
Chad Loder
Extremism researcher
I worked with @buttondown and asked for some new payment support beyond the supporter single tier / pay-what-you-want options. Justin was great and built it in just a couple days.
Dan Hon
Author & consultant
I write nonfiction and I use @buttondown - indie, GREAT personal customer support, very nice default styling, all the options I want including ones to protect my readers' privacy
Sumana Harihareswara
Open source maintainer
I use @buttondown because it does exactly what I need (manage subscribers and send markdown emails), not more and not less 👍 As a bonus it's made by an indie dev which I love!
Max Stober
Founder, GraphCDN
If you’re considering running an email newsletter, or if you already run one and are considering a change of provider, I highly recommend @buttondownemail. Super-easy app, very fair pricing with a generous free tier, and exemplary support. 💯
Peter Gasston
Technologist and speaker
imo @buttondown is easily one of the best-designed services i’ve used in recent years, if you have a substack you should really consider switching!
Kabir Goel
Engineer, Cal
Thanks for getting me excited about email newsletters again.
Garrick van Buren
I'm very thrilled that I can just write in Markdown without having to deal with email builders and all that crap.
Parham Doustdar
Thanks again for all the help! You’ve really turned something super complex into something super easy – sending new issues is as simple as firing off a text message.
Kartik Chaturvedi
Thanks for creating a simple way for people who want to, like, put words in a hole and have it sent to people... I am just thankful that something just nice and human exists on the internet.
Emmanuel Quartey
I tried 3 other newsletter services today and I felt like wanting to rip my hair out. They were all painfully slow. I'm so glad I found Buttondown.
Mohamed Elbadwihi
I’ve found Buttondown to be a great fit for my workflow and have been delighted by all of Justin’s thoughtful features and improvements to the product.
Michael Lee
Like seriously, so many lovely little easter eggs in one could-be-boring service.
Alexandra Muck
I just switched over from Tinyletter and I'm really excited to have found a place to host my tiny newsletter that doesn't seem like it's assuming everyone sending newsletters is an email marketer / growth hacker.
Tessa Alexanian
I'm in love with the simplicity of Buttondown.
I’ve used similar tools in the past and Buttondown is by far the simplest to use and most promising.
Fabrizio Rinaldi
Thank you for creating such a simple and brilliant tool. I’ve just signed up and the experience has been smooth and painless (the docs are great too!)
Oliver Holms
As a developer who has hated every email system I've ever used this is so nice.
Drew Hornbein
I wish I still wrote a newsletter just so I could use buttondown again. It’s like that.
Steven Kornweiss

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