Every December, somebody on the team pastes a Slack Christmas theme into #random, someone else replies "ooh, switching," and within an hour half the company's sidebars have gone evergreen and red. Nobody planned it. Nobody budgeted for it. It's just one of those small, visible, zero-cost rituals that make a workspace feel like a place where people actually live — and it's reliably one of the better low-effort morale wins of the month.
This is a gallery of twelve holiday and winter palettes for Slack's sidebar, each with a name, the vibe, the hex values, and a ready-to-paste theme string. There's a proper Christmas set, a couple of snow-and-ice themes, palettes for Hanukkah, Kwanzaa, and New Year's Eve, a deliberately loud Ugly Sweater, and a minimalist winter theme for the people who'd rather not. Grab what fits, share it with your team, and get back to shipping before the freeze.
How to Apply a Slack Holiday Theme (and Get Your Team to Match)
Open Slack, click your workspace name → Preferences → Appearance, expand Custom theme, and paste a string. Slack applies it instantly, no save button. If you want the step-by-step with screenshots, we published a companion piece this week on how to change your Slack theme.
Every string below uses the same eight comma-separated hex values, in the same order as in our best Slack themes roundup: column background, hover menu background, active item, active item text, hover item, text color, active presence dot, and mention badge. If you want to know exactly what each field paints so you can tweak one, Slack theme colors explained walks through all eight.
The sharing trick is the whole reason theme threads spread: paste a theme string as a message in any channel and Slack recognizes it and attaches a Switch sidebar theme button. One click and a teammate is matching you. Drop a string in #general with "holiday sidebars, anyone?" and let it snowball.
One honest caveat before the gallery: custom sidebar themes are a desktop and browser feature. The Slack mobile apps follow your system light/dark setting and ignore custom palettes, so your phone stays stock no matter how festive your laptop looks. Every theme below was checked for readable text against its column background — no light-on-light, no dark-on-dark — because a sidebar you can't read is a bad gift.
Classic Christmas Slack Themes
1. Classic Christmas
The tree, the holly, the ornaments. Deep evergreen sidebar, a red active channel, gold presence dots. The one most people mean when they search for a Slack Christmas theme.
Palette: evergreen #0F3D2E, holly red #C41E3A, gold #F4C542, snow text #E8F1EA
#0F3D2E,#14503C,#C41E3A,#FFFFFF,#175A44,#E8F1EA,#F4C542,#F4C542
2. Candy Cane
A light theme for people who don't want a dark sidebar in the darkest month. Peppermint-white column, bright red active channel, a green presence dot so it isn't all one flavor. Reads clean on a bright monitor.
Palette: peppermint white #FFF5F5, cane red #D7263D, wintergreen #2E8B57, maroon text #5A1A22
#FFF5F5,#FFE1E1,#D7263D,#FFFFFF,#FFD6D6,#5A1A22,#2E8B57,#D7263D
3. Cozy Cabin
Less "Christmas morning," more "the week between Christmas and New Year's when nobody is really working." Dark walnut sidebar, cream text, and an ember-orange active channel like a wood stove in the corner.
Palette: walnut #3B2A20, ember #E07A2F, warm gold #C9A96E, cream text #F1E6D6
#3B2A20,#4A3527,#E07A2F,#2B1A10,#55402F,#F1E6D6,#C9A96E,#E07A2F
4. Gingerbread
Mid-brown gingerbread, white-icing active channel, and gumdrop presence and mention colors. The most edible theme on the list. Surprisingly readable — the cream text on warm brown holds up over a long day.
Palette: gingerbread #7B4A2D, royal icing #FFF4E3, green gumdrop #A9D18E, red gumdrop #E5484D
#7B4A2D,#8C5738,#FFF4E3,#5A3320,#96603F,#FBE9D3,#A9D18E,#E5484D
Slack Winter Themes: Snow, Ice, and Aurora
Winter themes have a longer shelf life than Christmas ones. Nobody blinks at an icy blue sidebar in February, whereas the holly-and-gold one starts to feel like a neighbor who still has the lights up.
5. Winter Wonderland
Fresh-snow white with a glacier-blue active channel and slate text. Light, cold, calm. This is the theme you'll still have on in March and not mind.
Palette: fresh snow #EEF6FB, glacier #3A7CA5, ice #6FC3DF, slate text #1F3A4D
#EEF6FB,#DCEBF5,#3A7CA5,#FFFFFF,#E2EEF6,#1F3A4D,#6FC3DF,#2A5D7C
6. Northern Lights
Deep polar-night navy with an electric aurora-green active channel, violet presence dots, and a pink mention badge. The showiest palette here that isn't trying to be a holiday — pair it with dark mode and it's genuinely beautiful.
Palette: polar night #0B1A2A, aurora green #2EE6A6, violet #8A5CF6, aurora pink #FF6EB4
#0B1A2A,#122A3D,#2EE6A6,#0B1A2A,#173650,#CFE9E3,#8A5CF6,#FF6EB4
7. Midnight Snowfall
Two colors, basically: dark navy and white. The active channel is a bright white block with navy text, presence dots are pale blue, and the mention badge is snow-white. Elegant, quiet, and it makes unread mentions impossible to miss.
Palette: midnight #0E1A33, snow #FFFFFF, moonlight #9EC5FF, frost text #E6ECF7
#0E1A33,#172846,#FFFFFF,#0E1A33,#1C3055,#E6ECF7,#9EC5FF,#FFFFFF
Hanukkah, Kwanzaa, and New Year Slack Themes
Not every December is a Christmas December. If your team is celebrating something else — or several things at once — these three belong in the same thread.
8. Hanukkah Blue & Silver
Rich royal blue with a silver active channel and silver presence dots, white mention badge. It sidesteps the red-and-green entirely and looks sharp enough to keep past the eighth night.
Palette: royal blue #0D2B6B, silver #C0C7D4, bright silver #D9DEE8, white text #E9EEF8
#0D2B6B,#123A8A,#C0C7D4,#0D2B6B,#1A44A0,#E9EEF8,#D9DEE8,#FFFFFF
9. Kwanzaa
The three colors of the bendera: black column, a green active channel and presence dot, red mention badge. High contrast, bold, and one of the most legible dark themes in the set.
Palette: black #121212, green #00843D, red #C8102E, white text #F2F2F2
#121212,#1E1E1E,#00843D,#FFFFFF,#262626,#F2F2F2,#00843D,#C8102E
10. New Year's Eve
Black tie. Near-black column, metallic gold active channel with black text, champagne-colored channel names and presence dots. Apply it on the 26th and it carries you cleanly into January — a good Slack new year theme is one you don't have to remove on the 2nd.
Palette: tuxedo black #0B0B0F, gold #D4AF37, champagne #F7E7B4, champagne text #F3E9C6
#0B0B0F,#17171D,#D4AF37,#0B0B0F,#1F1F27,#F3E9C6,#F7E7B4,#D4AF37
Two for the Extremes
11. Ugly Sweater
You were warned. A loud red column, a kelly-green active channel, buttery-yellow channel names, and a yellow presence dot that looks like a pom-pom. Objectively too much, which is the point. Apply it for the office party, screenshot it, remove it by Monday.
Palette: sweater red #B22234, kelly green #1E7B3A, pom-pom yellow #FFD100, cream text #FFF4C2
#B22234,#8F1B2A,#1E7B3A,#FFFFFF,#9E1E2E,#FFF4C2,#FFD100,#1E7B3A
12. Minimalist Winter
For the person who muted the holiday thread. Cool light-gray column, charcoal text, and exactly one accent — a steel blue for the active channel and mention badge. It nods at the season without wearing a hat. If "festive" isn't in your vocabulary, this is your December.
Palette: overcast #F4F5F7, steel blue #5B7C99, pale sky #7FA3BF, charcoal text #3A3F47
#F4F5F7,#E8EAEE,#5B7C99,#FFFFFF,#EBEDF1,#3A3F47,#7FA3BF,#5B7C99
Making the Theme Thread Actually Work
A few things we've noticed from watching these threads play out in real workspaces:
- Post three, not twelve. A dark one, a light one, and a weird one. Choice paralysis kills the thread; three options gets people clicking within a minute.
- Use the button, not a screenshot. A pasted string gets the Switch sidebar theme button; a screenshot gets "how do I do that?" replies. If you're not seeing the button, check for a stray space or a missing
#— Slack silently ignores malformed strings. - Let people opt out loudly. Themes are personal and per-workspace, so nobody's forced. Including Minimalist Winter in the thread gives the theme-averse a way to participate without participating.
- Pair dark themes with dark mode. Custom themes color the sidebar only; the message pane follows your light/dark setting. Northern Lights over a white message pane looks unfinished.
- Set a reminder to change it back. Or don't, and enjoy the Ugly Sweater in April. Your call.
Pair It With a December Recognition Ritual
A holiday theme is a nice ten-second gesture. The reason it lands is that it's shared — a visible sign that the people in this workspace are paying attention to each other. That same instinct, pointed at people instead of pixels, is what makes December the best month of the year for recognition. A few rituals that pair well with a freshly themed sidebar:
- End-of-year shout-outs. One thread, one prompt: "Who made your year easier?" Every reply names a person and a specific thing. We wrote a longer playbook on closing out the year with recognition, including how to do it without it turning into a popularity contest.
- A shout-out advent calendar. One recognition a day from December 1st through the holiday break, rotating who kicks it off. Full disclosure, this is where our product comes in — Propsly (yes, ours) is a Slack recognition bot where anyone types
/props @maria +20 for shipping the migration #teamwork, every give lands in a feed channel like#wins, and each person gets 200 props a month to hand out. An advent calendar of one/propsa day, in a channel everyone reads, builds a two-week highlight reel of the year with zero admin effort. It's free for unlimited users. - A year-in-review thread. Ask every team to post their one proudest ship of the year, plus the person outside the team who helped most. That second half surfaces the cross-team work that never makes it into an all-hands slide.
- Written notes, not just points. Points are the mechanism; the sentence is what people remember. If you're stuck on wording, we collected holiday recognition messages for remote teams you can steal and personalize.
Whichever you choose, the pattern is the same as the theme thread: low effort, high visibility, easy to join. That's the recipe behind most of the Slack rituals that give distributed teams a pulse, and December is when teams have the most slack — sorry — to try one.
So: pick a palette, paste it in a channel, watch the switch button do its thing. Then, while everyone's sidebars are matching and the mood is briefly, collectively festive, ask the team who made their year. The theme comes off in January. The other part tends to stick.