Good dark mode email design starts from the fact that you can't fully control it. Some inboxes use your dark styles, some recolour the email themselves, and some leave it alone. Pick a logo and brand colours that read on both light and dark, keep the important words in live text, and check a real test in dark mode before you export.
You signed the email off in light mode. Then someone opens it on their phone at night, the black logo has vanished, the white card has turned grey and the button looks like it belongs to a different brand. What you want is a design that still looks like you in dark mode. Milo Email Studio helps on both sides of that: your brand kit gives every email colours and a logo you've already checked, and each email has a setting that asks the Gmail apps to show your light design as you built it.
In short
- Inboxes treat dark mode in three ways: use your dark styles, recolour the email for you, or leave it light.
- Logos on transparent backgrounds and very dark text are what break first.
- Since September 2026 the Gmail apps keep the light design for readers on a Google account when the email asks for it. Milo Email Studio has a setting for that.
- It's best effort, so a real test in a dark-mode inbox still matters.
Why your email looks different in dark mode
There isn't one dark mode. Each inbox decides for itself what to do with your email when the reader's phone or computer is set to dark.
Some read the dark styles you put in the email. According to Can I email, Apple Mail, Outlook for Mac, Outlook on iPhone, Outlook on the web and recent versions of Samsung Email all do. Others recolour the email on their own. The Gmail apps have done this for years: the Android app darkens colours, and the iPhone app inverts them, so an email that starts out dark can end up light. And some largely ignore dark styles, including classic Outlook on Windows, Gmail on the web and Yahoo.
Here's how that looks side by side. Where the sources don't say, we've written "not documented" rather than guess.
| Inbox | Reads your dark styles? | Recolours on its own? | Honours a light only request? |
|---|---|---|---|
| Apple Mail (Mac and iPhone) | Yes | Not documented | Yes on Mac; not documented on iPhone |
| Gmail apps, Google account | No | Yes | Yes, since September 2026 |
| Gmail apps, other accounts | No | Yes | No |
| Gmail on the web | No | Not documented | No |
| Outlook for Mac, iPhone and web | Yes | Not documented | No |
| Classic Outlook on Windows | No | Not documented | No |
Sources: Can I email's dark styles and color-scheme pages, and the Email Markup Consortium's Gmail app dark mode update.
What breaks first, and why it matters
The things that go wrong in dark mode are the things readers notice.
A black logo saved as a transparent PNG sits straight on the inbox's dark background and disappears. Grey body text loses its contrast when the background flips. Your brand colours shift, so the button that's always been your shade of green comes out a muddier one and the email stops looking like you. And an image with a white background baked in shows up as a bright box in the middle of a dark email.
None of these break the email outright. They just make it look less like your brand, at the moment someone's deciding whether to read on.
Design choices that survive the flip
You can't stop every inbox from changing your colours, but you can pick ones that come through it well.
- Give the logo something to sit on. A solid background behind it, or a thin light outline, keeps a dark logo visible whatever colour the inbox puts behind it.
- Use mid-tone brand colours for buttons and accents. Very dark and very light colours change the most when an inbox recolours. Mid-tones tend to survive partial recolouring and still read as yours.
- Keep the important words in live text. The offer, the date and the button label should be text, not part of an image. Text gets recoloured to stay readable. Words baked into a picture don't.
- Set backgrounds properly. The full HTML email checklist covers how, along with the other checks worth doing before you export.
The easiest place to make these choices is once, in your brand kit. When you set your colours once in a brand kit, every new email starts from a palette, buttons and a logo you've already seen in dark mode, so you're not re-checking the same things on every send. If you design seasonal emails, the same thinking applies to dark Halloween palettes.
The Gmail change, and when to keep your light design
In September 2026 the Gmail apps on iPhone and Android started honouring a light only color-scheme request in an email. When an email carries it, the app shows the email as designed instead of recolouring it. The Email Markup Consortium notes that this only applies to emails received into Google accounts, meaning @gmail.com and Google Workspace addresses. Other accounts added to the Gmail app still get the automatic recolouring.
That doesn't mean every email should ask for it. The reader chose dark mode, and a bright white email at midnight isn't what they asked for. It's worth keeping your light design when the recolouring really hurts the email: a logo that vanishes, brand colours that matter to the message, or a dark design that the iPhone app would otherwise turn light. If the automatic version still looks like you, it's fine to leave it alone.
Keep your light design in Milo
Each email in Milo Email Studio has a setting called "Keep my light design in the Gmail apps", in the email's settings. Turn it on and the email asks the Gmail apps, and other dark mode inboxes that read the request, to show your light colours as designed.
It goes with the email everywhere it leaves Milo: the HTML or MJML you download or copy, your Test sends, the Zoho Campaigns draft and emails sent from Milo flows. It's off unless you turn it on, and it's per email, so a dark-designed promo and a light newsletter can each be treated the way that suits them.
It's best effort. The Gmail apps honour it only for Google accounts, and some apps may still change your colours. That's why the design choices above still matter, and why a Test in a dark-mode inbox is still the real check.
The editor canvas and review links show your design as built, so check dark mode in a Test rather than in a preview.
How we checked this
On 19 October 2026 we exported the same Milo email, built from the Christmas gifts starter, as HTML and MJML with the setting off and then on, and compared the files. With the setting off, both files were byte for byte identical to an export made without it. With it on, the only difference was the light-only color-scheme tags added at the top of the email's head. This was a check of what Milo exports, not an inbox test, so how each inbox treats the request comes from the sources linked above.
Where Milo fits
Design on the drag-and-drop canvas with your brand kit, with the AI designer on hand if you'd like a first draft. Send yourself a Test and open it on your phone in dark mode. If the logo or a colour doesn't hold up, adjust the kit or the block, or keep your light design for that email, and send another Test. If someone else needs to approve it, you can get sign-off from a preview link.
When it looks right, export ready-to-send HTML or MJML for your ESP (here's HTML or MJML: which file to export), or push a draft straight to Zoho Campaigns. The campaign itself goes out from your ESP. If your list includes classic Outlook too, here's why Outlook-safe tables still matter.
Try it on your next email.
Questions
Why does my logo disappear in dark mode emails?
A dark logo on a transparent background sits straight on the inbox's dark background. Give it a solid background or a light outline, and check it in a dark-mode test.
Does Gmail support dark mode in emails?
Gmail doesn't read your own dark styles. Its iPhone and Android apps recolour the email themselves, but since September 2026 they show your light design instead if the email asks for light only and the reader uses a Google account.
Can I stop dark mode from changing my email's colours?
Partly. You can ask inboxes to keep your light design, and the Gmail apps now honour that for Google accounts, but some apps will still recolour the email. Design so it reads either way.
How do I keep my light design in dark mode with Milo?
Turn on "Keep my light design in the Gmail apps" for that email. Your exports, Test sends, Zoho Campaigns drafts and flow emails then carry the request. It's best effort, so send a Test and check it on your phone.
Should I keep emails light for dark mode readers?
Only when the recolouring hurts the email. The reader chose dark mode, so if the automatic version still looks like you, leave it.
How do I test an email in dark mode?
Send yourself a test and open it with your phone and computer in dark mode, in the inboxes your list really uses.