Published by the Zolyp team ·
How do you add a topic tag in the Threads app?
Threads' help centre gives the same steps for iPhone and Android:
- Tap Add (the plus icon) at the bottom to start a new thread.
- Tap Tag, or type #, then enter a topic. You can also choose one of the trending topics that appear.
- When you're ready, tap Post in the bottom right. The topic you tagged appears in blue.
- To tag without the # symbol, just type the topic (for example: cats)
- To keep the # symbol, type # as the first character (for example: #cats)
Source: Instagram Help Centre: Tag a topic in your post on Threads, checked 15 October 2026
How do you add a topic tag on threads.com?
On a computer the steps are almost the same:
- Click Add in the bottom right to start a new thread.
- Click Tag, or type #, then enter a topic or choose a trending one.
- Click Post in the bottom right. The topic shows in blue in your post.
Sources: Instagram Help Centre: Tag a topic in your post on Threads, checked 15 October 2026; Instagram Help Centre: Start a new thread on Threads, checked 15 October 2026
What are the rules for Threads topic tags?
Threads' help centre lists these limits:
| Rule | What Threads allows |
|---|---|
| Topics per post | 1 |
| Length | Up to 50 characters |
| Spaces and symbols | Allowed, so a phrase like small business tips is one topic |
| The # symbol | Optional. Meta notes it may add functions on other fediverse platforms |
| What a tap does | Shows search results for posts on that topic |
Source: Instagram Help Centre: Tag a topic in your post on Threads, checked 15 October 2026
How do topic tags connect to communities?
Threads communities grow out of popular topic tags. Meta's help centre says that as people add a tag to their posts and profiles, activity builds, and once engagement is high enough the topic can become an official community, subject to review. When we checked, communities were a beta being tested across more than 200 of the most popular topics.
An active community's tag turns blue with a custom icon. You can post into a community by adding its tag, and relevant posts may be surfaced in a related community even without one. You can also add up to 100 topics or communities to the Interests section of your profile, which is public.
Sources: Instagram Help Centre: About communities on Threads, checked 15 October 2026; Instagram Help Centre: Manage your Threads profile, checked 15 October 2026
How should a business choose its topic tag?
Meta doesn't publish advice on picking tags, so these are our suggestions:
- Pick the topic a customer would tap, such as your product category or the problem you solve, rather than your brand name
- Tap the tag on someone else's post first and check the posts there match yours
- Reuse the same few topics, so your posts and profile point at a clear subject
- If a community exists for your field, use its tag so members can find the post
Why can't you add a topic tag?
Threads doesn't allow tagging some topics when the content linked to them consistently goes against its Terms of Use or Community Standards. Meta says it reviews these topics from time to time and may allow them again. Other reasons a tag won't work:
- The post already has a topic. Each post can carry only 1
- The topic is longer than 50 characters. Shorten it
Sources: Instagram Help Centre: Why tagging certain topics isn't allowed on Threads, checked 15 October 2026; Instagram Help Centre: Tag a topic in your post on Threads, checked 15 October 2026
Writing the post behind the tag
Disclosure: this is our product. A tag helps people find a post, but the post still has to be worth reading. Zolyp plans and writes short Threads posts in your brand's voice around the content themes you set, and publishes them once you approve each one. There's a 3-day free trial, no card required.
Common questions
How many topic tags can you use on Threads?
One per post. Threads' help centre says you can include up to 1 topic in each post.
Do Threads topic tags need a # symbol?
No. You can type # first or leave it out. Both work, and the topic can include spaces.
How long can a Threads topic tag be?
Up to 50 characters, including spaces and special characters.
Are Threads topic tags the same as hashtags?
They do a similar job, linking your post to others on the same subject. The differences are that Threads allows only one per post, and a topic can include spaces.
Why is a topic unavailable to tag on Threads?
Threads blocks tagging of topics whose content consistently breaks its Terms of Use or Community Standards, and reviews those topics periodically.