Ugh. You've asked the hairiest possible question about modern English. There is no simple or definite answer here. As far as I see it, when you mean the possession of something ,"I've got" is a colloquial spoken form, and "I have" is the standard form for speaking and writing. "I've got" in writing makes me think something happened in the past to explain your current possession. Use "I have" for natural possession (eg. a description of yourself). I myself don't like "I've got", and I'm irritated that it's being taught as 'standard' English (ie. as the written and spoken form) to ESL-learners. However, it's simply naïve to assume "I've got" is wrong (or confined to one style of English); the fact is, native English speakers use it in speech abundantly. The last time I was home in Australia, I paid special attention to how people spoke, and I assure you that "I've got" is epidemic. Not to mention its use in movies, TV shows and songs... so yes, in that context both expressions are interchangeable. Advice? Keep "I've got" for colloquial speech, but for a proper standard, use "I have".

In the present tense they are generally interchangeable. I have got a new car. I have a new car. Both mean the same thing. However, in the future tense we just use 'have' Me: Have you got those concert tickets yet? Friend: Not yet. Me: Will you have them by tomorrow? In this case if I said, 'Will you have got them by tomorrow?' it would sound strange. Hope that helps!

I try to use got seldom. There is always a way around got. Try to stick with I have.

Never use I have got, its wrong. I have, thats it. :)

They are interchangeable.