Built around newsletters, not inbox triage.
Email clients are excellent for sending, replying, forwarding, and getting through messages. Letterboxx is built for reading, collecting, highlighting, and returning to newsletters.
A newsletter app that works with the email you already use.
Letterboxx turns newsletters from selected email folders into local reading copies, so your inbox can keep doing its usual job.
Read without living in your inbox.
A calmer reading space for the newsletters you want — not your everyday email.
Turn newsletter clutter into a library.
Create Letterboxxes for topics, writers, projects, or anything you want to keep together.
Let recurring newsletters sort themselves.
Route each sender, subject, or newsletter type to the right Letterboxx automatically.
Remove the clutter. Keep the writing.
Clean View trims trackers, ads, embeds, and messy email HTML for a calmer read.
Highlight what you want to remember.
Save useful passages in familiar colors and find them again later.
Come back to what matters.
Favorite a newsletter, set a reminder, or move it somewhere you’ll find it next.
Protect the library you’re building.
Encrypted backups preserve newsletters, Letterboxxes, rules, highlights, and settings.
See your reading life at a glance.
Track what arrived, what you’ve read, and the library you’re building.
A reader that belongs on your Mac.
Choose light, dark, e-ink, newspaper, and other themes designed for comfortable reading.
Keep email for communication. Give newsletters a reading library.
Newsletter subscriptions already arrive through your email account. Letterboxx connects to the account and folders you choose, then saves local newsletter copies in its own reading library. The original messages stay on the mail server unless you explicitly delete them; organizing in Letterboxx changes the local reading copy, not your mailbox.
For the full source-to-library model, read how Letterboxx works. If you are deciding whether you need a separate reader at all, start with the email newsletter reader explanation; for the Mac-specific experience, see the newsletter app for Mac.
Works with the mail you already use.
Connect Gmail or IMAP accounts, choose the folders that contain newsletters, and download local copies while original messages remain on the mail server unless you delete them.
A searchable library for saved ideas.
Sort recurring newsletters into Letterboxxes, use Clean View when email HTML gets messy, save highlights, and search across the issues you have kept.
Keep email for communication. Use Letterboxx for subscribed reading.
An email newsletter app should not make you abandon your inbox. Letterboxx works beside the email accounts you already use, importing local copies from selected folders so newsletters can become a reading library without changing where the original messages live.
That also makes it easier to organize email newsletters by topic, sender, or habit once they are outside the inbox. For exact source-folder and original-message behavior, read how Letterboxx works.
- Connect the account that receives newsletters. Gmail and IMAP accounts can provide the folders or labels where newsletters arrive.
- Choose only newsletter sources. Import from the places that contain subscriptions, not every message in your mail account.
- Read, organize, highlight, and search. Letterboxx turns recurring issues into collections you can revisit after the inbox has moved on.
Jason Snell’s Pick of the Week!
Jason Snell picked Letterboxx as his Pick of the Week on the August 11, 2026 episode of MacBreak Weekly.
Watch Jason Snell talk about Letterboxx on MacBreak Weekly.
MacBreak Weekly © TWiT, LLC. Used with permission. TWiT.tv
What an email newsletter app should make easier.
The point is not to replace email. The point is to give newsletters the reading tools that email clients usually hide behind mail-management workflows.
Sort subscriptions by topic, sender, or reading habit.
- create Letterboxxes for topics like tech, investing, local news, or essays
- route recurring senders with Auto-Delivery rules
- filter by reading state, highlights, sender, or favorites
Keep useful ideas available after the issue is read.
- save highlights directly inside the newsletter reader
- use Clean View when newsletter HTML gets noisy
- search the local library when you remember an idea but not the issue
Email is for communication.
Letterboxx is for reading.
Your email inbox is built for messages, replies, and triage. Letterboxx is built for essays, digests, roundups, research, and the publications you actually meant to revisit.
Connect your email. Read local copies.
Pick the mail folders that contain the things you want to read. Letterboxx downloads local copies into your Mac reading library, while original messages remain on the mail server unless you delete them.
Your newsletters do not change.
The way you use them does.
Instead of treating every newsletter like another inbox item, Letterboxx turns recurring subscriptions into collections you can read, highlight, search, and keep.
Your inbox is good at
- Sending and receiving messages
- Replying and forwarding
- Processing the inbox
- Getting back to zero
Letterboxx helps you
- Build collections around topics
- Route newsletters automatically
- Highlight useful ideas
- Search across years of saved issues
- Read without inbox chaos
Download Letterboxx for Mac.
Start with 14 days free before deciding.
Take a tour of your newsletter library.
Click through Dashboard, Newsletter, Clean View, Message Diagnostics, Backup & Restore, and Highlights to see how Letterboxx turns email newsletters into a calmer Mac reading space.
Letterboxxes
Letterboxxes are your custom newsletter folders inside Letterboxx. Create focused spaces for each topic, then file newsletters manually or route them automatically with Auto-Delivery.
Give every newsletter a purpose-built home.
Separate your reading stream into intentional Letterboxxes so your inbox stays clean and your best newsletters stay easy to find.
- Create Letterboxxes for topics, projects, or interests
- Move newsletters directly into a Letterboxx using the contextual menu or drag and drop
- Use Auto-Delivery rules to route new messages into the right Letterboxx automatically
Create and manage Letterboxxes in seconds.
Letterboxxes live directly in the sidebar and can be created on demand, so setup and organization stay one click away.
- Open sidebar actions to create and manage your Letterboxxes instantly
- Name and configure a new Letterboxx in a focused modal flow
- Keep your Letterboxx system aligned with how you actually read using sort or drag and drop
Clean View
Newsletters should feel like reading, not like loading a miniature website full of scripts, embeds, and tracking pixels. Clean View gives you a calmer reader with visible privacy reporting.
Strip the noise before it reaches your attention.
Clean View removes common newsletter clutter and keeps a local audit of what was taken out so the reader stays fast, quiet, and explainable.
- Blocks or sanitizes trackers, ads, scripts, autoplay media, embeds, and remote images
- Tracks per-message, sender, and all-newsletter removal counts
- Offers Off, Medium, High, and Custom privacy modes for different reading preferences
See the work happening behind the quiet.
The Clean View settings pane surfaces cumulative totals and attribution so privacy protection feels transparent instead of mysterious.
- Totals for observed messages, sanitizer removals, trackers and ads, and privacy intelligence
- Source attribution for blocking-list matches when Letterboxx can map them locally
- Backfill tools for keeping Clean View reporting accurate across older newsletters
Diagnostics without leaving the reader.
When a newsletter looks different than expected, Letterboxx can explain the message, Clean View changes, delivery state, and source details right beside the reading flow.
Inspect the current newsletter inline.
Message Diagnostics now flips into the reader pane, so you can understand a selected newsletter without opening a separate utility window.
- Review identity, composition, raw source availability, and Clean View summary details
- Use the same toolbar and keyboard path from the reader
- Keep diagnostics tied to the newsletter you are already reading
Keep delivery and maintenance visible.
Activity Center gives important app events a dedicated place, so import, routing, highlight, and maintenance details stay understandable.
- Review recent activity when delivery or rendering needs context
- Keep diagnostics and operational events separate from focused reading
Automation, accounts, and safekeeping.
Letterboxx is still local-first, but it gives you practical controls for routing newsletters, importing copies from mail accounts, choosing read-status behavior, and protecting your library.
Rules that keep the library tidy.
Auto-Delivery routes new arrivals into the right Letterboxx using ordered rules you control.
Clear setup, honest sync status.
Connect Gmail or IMAP accounts, import newsletter copies from selected folders, and see what iCloud-backed continuity can do when available.
A real safety net for your reading library.
Create encrypted backups for newsletters, Letterboxxes, Auto-Delivery, highlights, reminders, and settings.
Appearance
Tune Letterboxx to your reading style with theme controls, typography settings, and calmer visual defaults.
Choose the look that matches how you read.
Switch themes instantly and keep your reading experience aligned with your environment and focus level.
- Theme modes include System, Light, Dark, Newspaper, E-Ink, and Tiger
- Quickly preview and switch without leaving your reading flow
Tune sizing, density, and visible detail.
Adjust the newsletter list so it surfaces exactly the information you want at a glance.
- Choose the list font and row density
- Set subject size, secondary text size, and sender badge size independently
- Toggle sender name, date and time, status indicators, and unread indicator visibility
Highlighting
Save important passages in any newsletter, keep them attached to that message, and use View Highlights to jump through them later.
Save the passages worth coming back to
Select text in the reader and save it as a highlight without leaving the newsletter.
- Highlights stay attached to the newsletter where you saved them
- Use View Highlights to jump through saved passages in order
- Recolor or remove highlights whenever you revisit the message
Find newsletters with saved highlights later.
The Highlighted filter shows newsletters that contain saved highlights, so the ideas you marked are easy to find again.
- Highlights persist per message across app sessions
- The Highlighted filter shows newsletters with saved highlights
- Recolor or remove highlights whenever you revisit the message
Email newsletter app FAQ
Is Letterboxx an email client?
No. Letterboxx is a dedicated Mac app for reading and organizing newsletter copies. Your normal email app still handles everyday mail, replies, and sending.
Does Letterboxx move my original emails?
No. Letterboxx connects to your email account using IMAP and downloads local newsletter copies into a reading library on your Mac. Original messages remain on the mail server unless you explicitly delete them.
Can I organize newsletters into folders?
Yes. Letterboxxes are topic-based spaces for newsletters. You can file newsletters manually or use Auto-Delivery rules for recurring senders.
Can I highlight passages in newsletters?
Yes. You can select useful passages, save highlights in familiar colors, and return to highlighted newsletters later.
Is there a free trial?
Yes. Letterboxx offers a 14-day free trial before you choose a monthly or annual plan.