The important thing to remember is

Grammatically, this phrase is quite sturdy. You usually follow it with the word is, and then a clause (a full mini-sentence). Most people include the word that after is, though in casual speech, you can drop it. For example: The important thing to remember is that the password expires tonight. You are setting up a noun phrase as the subject (The important thing to remember), using is as a bridge, and then delivering the payload. It works best when you've already provided some context. If you just walk up to someone and say this phrase without a back-story, they’ll be confused. It is a tool for summarization and emphasis. Think of it as the 'TL;DR' (Too Long; Didn't Read) of spoken English.

This phrase sits comfortably in the 'Neutral' to 'Formal' categories. You’ll hear it constantly in office meetings, Zoom calls, and academic lectures. It’s the bread and butter of managers and teachers. However, it’s not so stiff that you can’t use it with friends. If you’re giving a buddy advice on a breakup or explaining how to beat a difficult boss in a video game, it fits perfectly. It suggests that you have thought about the topic and filtered out the noise for them. It’s slightly more formal than saying Just don't forget..., but much less intimidating than It is of the utmost importance that you recall... unless you're a Victorian ghost.

You see this all over the internet. On YouTube tutorials, a creator might spend ten minutes showing you how to edit a photo, but then they'll end with, the important thing to remember is to save your work in high resolution. It’s the 'pro-tip' signal. In LinkedIn posts, influencers use it to break down complex business strategies into one digestible nugget. Even on TikTok, when someone is giving a 'storytime' about a crazy date, they use it to emphasize the moral of the story. It’s the sentence that everyone remembers after the video ends, even if they forgot the rest of the chatter.

Use this when you feel like your main point might be getting lost in the details. It’s perfect for the conclusion of a presentation or the end of a long set of instructions. If you are training a new colleague at work, use it to highlight safety protocols or 'unwritten rules' of the office. It’s also a great way to regain control of a conversation if things have gone off-track. By using this phrase, you are essentially saying, 'Let's get back to what actually matters here.' It’s a leadership phrase; it shows you know how to prioritize information.

Don't be the person who uses this for every single sentence. If everything is 'the important thing,' then nothing is. It loses its power if you over-apply it. Also, avoid using it for trivial things unless you are being intentionally funny. Saying the important thing to remember is that I like my toast slightly burnt to a waiter might come off as a bit dramatic or high-maintenance. Lastly, avoid using it in very high-stakes emotional arguments where it might sound condescending. In those cases, it can feel like you are lecturing the other person rather than talking with them. Use it to guide, not to patronize.

A very common error for learners is mixing up the grammar after the phrase. Some people say ✗ The important thing to remember is remember the key → ✓ The important thing to remember is to take the key. You need that to or a that clause. Another mistake is using the gerund form: ✗ The important thing for remembering is... While technically understandable, it sounds very clunky and unnatural to a native speaker. Also, keep an eye on the word order. Don't say ✗ To remember the important thing is... unless you're trying to write a very confusing poem. Stick to the standard sequence for maximum clarity.

Depending on where you are and who you're talking to, you might hear different versions. The key thing is... is a very common, slightly shorter alternative. If you want to sound even more professional, you might say, The critical takeaway here is... In a very casual setting, people often just say, The thing is... or Bottom line is... In British English, you might hear The main point to bear in mind is..., which sounds a bit more sophisticated. For the Gen Z crowd, you might just hear The main thing is... followed by a very direct statement. They all do the same job: they act as a verbal spotlight.

Is this phrase too long for texting? Usually, yes. In a text, you’d probably just write The main thing is... or Remember that.... Does it have to be a 'thing'? Yes, thing is the standard noun here, though point or fact works too. Can I use it in an essay? Absolutely! It’s a great transition phrase to use in a concluding paragraph to reinforce your thesis statement. Just make sure the 'thing' you are highlighting is actually important, or your teacher might give you a funny look. It's a powerful tool—use it wisely!