February 2021 update:

Slack officially added support for indented lists

Format your messages with indented lists

When formatting your messages in Slack, you can now indent up to five lines in ordered and bulleted lists. ...

As a workaround, I turned off automatic formatting - since it irritated me anyway - and then I can use the plain old

* something
  * nested something
* something else

which renders with asterisks as it appears here - but since I need the nested structure more than the fancy bullets, it's better than nothing.

EDIT: 🤦‍♂️ I just realized you can very simply do this using the actual bullet • character

• something
  • nested something
• something else

it will look pretty good in Slack too:

Inserting the • character is very simple using Compose key on Linux:

<Multi_key> <period> <equal>            : "•"   enfilledcircbullet # BULLET

(AltGr + . + =)

Here's a suggestion for indented messages in Slack:

Add a custom emoji that's just a transparent image (ex: ) and use it to indent your messages (if you want a bullet per se, you can always use another emoji like :black_small_square:)

Is there a way to do nested bulleted lists with the new Slack markdown / formatting tools?

No official way, but hopefully soon. (mirror 1, mirror 2):

We don't support nested bullets at the minute [...], but we're hoping to support nested bullet points properly in future.

When you create a post, you can have nested bullet lists. You need tor press - or *, then <TAB> key to increment your level:

Unfortunately, it does not work with messages.

You can do this by adding :blank: emoji and :dot: emoji I've set this up in two minutes:

blank image^^^ (can you see it???)

Dot image^^^

2022 update

One way:

1. Type an asterisk *
2. Press space, then
3. press tab

Another way:

1. Create a bullet point:

2. Press tab to indent it

Notes

• The indent must be created before adding text to the bullet
• Information from here

Tabs did not work for me as of the time of this posting. I use the "Format messages with markup" option in Slack so I don't have the text formatting toolbar.

I can't even add a tab character, as it just moves cursor focus to the send button. I copy/pasted tabs in, and that didn't seem to work either, but I found an obvious solution.

Just add four spaces in front of the * to indicate nested lists. For example:

* item
    * nested 
        * nested nested

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