Advise vs Let you know

When to use each in English, with meaning, register, and examples.

Advise

Top 2,000 (common)B1verb

Let you know

Top 1,000 (very common)
Most common: Let you know
 AdviseLet you know
Pronunciation🇬🇧 /["/ədˈvaɪz/","/ədˈvaɪzɪz/","/ədˈvaɪzd/","/ədˈvaɪzɪŋ/"]/🇺🇸 /["/ədˈvaɪz/","/ədˈvaɪzɪz/","/ədˈvaɪzd/","/ədˈvaɪzɪŋ/"]/🇬🇧 //lɛt jʊ nəʊ//🇺🇸 //lɛt jə noʊ//
MeaningTo give someone a suggestion about what they should do.To tell someone information later.
ExampleI advise you to finish your homework before going out.I will let you know as soon as I have more information.
RegisterNeutralNeutral
How commonTop 2,000 (common)Top 1,000 (very common)
CEFR levelB1-
Part of speechverb
Collocationsstrongly, badly, wrongly, about, against, on, be ill advised to do something, be well advised to do something, strongly, badly, wrongly, about, against, on, be ill advised to do something, be well advised to do something, be pleased to, regret to, of, keep somebody advisedlet you know later, let you know soon, let you know when, let you know tomorrow
Antonymsignore, neglect, disregard-
Common mistakesConfused with 'advice'; 'advise' is a verb, 'advice' is a noun., Using 'advise' without an object, e.g., saying 'I advise' without stating who or what., Incorrectly using 'advise' in informal settings when a simpler word like 'tell' would work better.Using 'let you know' instead of 'let me know' when speaking about oneself., Confusing 'let you know' with 'let you see' – they have different meanings., Forgetting to follow up on the promise to inform someone.
Usage notesUse 'advise' in professional, academic, or personal contexts when offering guidance. Avoid using it in casual conversation where 'suggest' may feel more appropriate.Commonly used in informal speech to indicate that you'll inform someone about something. Suitable in both personal and professional contexts.

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Let you know

Frequently asked questions: Advise vs Let you know

What's the difference between Advise and Let you know?

Advise: To give someone a suggestion about what they should do. Let you know: To tell someone information later.

Which is more common: Advise and Let you know?

Let you know is the most common in everyday English.

Can you show an example of each?

Advise: I advise you to finish your homework before going out. Let you know: I will let you know as soon as I have more information.

Can I use Advise and Let you know interchangeably?

Not always. Advise and Let you know are related and overlap in some contexts, but they differ in register, how common they are, and usage, so swapping one for another can change the meaning or tone. Check the differences above before substituting.

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