Question: I know that most of the people use "I belong to ABC" but I have seen "He is hailing from Mardan". So, Is there any difference?

Also, can I say "I belong to Swat" or "I belong to Mingora"? Swat is the name of my district while Mingora is the city where I live.

Answer: 
In American English, one would usually just say 

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> 1 I am from Mingora, Swat. 
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> 2 I am from Swat. I am from the Switzerland of the East. I am from Pakistan. 
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We don't usually say 

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> ? 3 I come from somewhere. 
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But we can say that to stress that we are not from the place that we are currently in. 

> 
> 4 I come from Mingora, remember, and people from Mingora have different customs than the people here do. 
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In American English we rarely say 

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> ?5 I belong to a place or to a company. 
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I do know where you heard *I belong to ABC*, but this is not the normal way in American English to say 

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> 6 I work for ABC. 
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*Hail from* indicates origin, as in 

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> 7 She hails from Mingora, Swat 
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Two answers here have labelled *hail from* as 'formal'. However most dictionaries of American English do not indicate this. And as a native speaker of American English, I would not call *hail from* 'formal'. See also my question on ELU: [Is *hail from* necessarily formal?](https://english.stackexchange.com/questions/317307/is-hail-from-somewhere-necessarily-formal-english). I have included links in that question to dictionaries which say *hail from* is formal. (Thanks to Khan for those links.)

To me, *hail from* sounds colloquial, something that Mark Twain, in informal usage, might say. But many newspapers and magazines use it today.
I hail from Swat vs I belong to Swat

If you want to say that some place is your place of birth, or the place where you live, you usually use the phrasal verb "come from'. For example:

I come from Swat.

You can also use the phrasal verb "hail from" instead, but it's usually used in formal English.

As for the use of the phrase 'belong to' in this sense, it's correct grammatically, though old-fashioned. It's true that we usually use this phrase in this sense in Pakistan.