The three phrases are just different ways of saying the same things, just some are more formal than others. I have to go - Casual but much more formal than I gotta go. I need to go - Same as above I gotta go - something I would say to my friends on chat or if I meet them in the street and need to leave quickly. Corrections to your question: "I have to go" vs "I need to go" vs "I gotta go". Do these three sentences have the same meaning? I usually watch some series and it´s very common to hear: "I gotta go". However, I think that these three expressions have the same meaning. Is that true or not? Ps.: I would be glad if you guys also could help me by correcting my mistakes in my question. Thanks in advance. PS. Your english is great!

Thank you for you comment and tips Geoff. This really helps.

To correct your initial question, the following is the correct grammar and tense. Does these three sentences has the same meaning? (Incorrect) Do these three sentences have the same meaning? (Correct) Does would be used if you were referring to one sentence (singular) Using the words do and have are used as you are talking about more than one sentence (plural) I hope this helps!