find someone you dont' like who is having thanksgiving and tell your unwanted guests that person's address and say that is where you are spending thanksgiving.<br />
or follow onewithjc's advice.
Say, "oh, I'm so sorry, I have other plans" (meaning, plans with someone who isn't you).<br />
Then say, "Maybe we can get together another time?" <br />
If they press you say, "Listen, I didn't plan on having people over. I won't be hosting any sort of dinner here FOR YOU."
I guess first off how did they think they were naturally invited ... have they spent previous Thanksgivings or other holidays with you? Do they know you don't like being with them or are you cordial whenever you are together? Short of being blunt with them and tell them they are not invited to your house for Thanksgiving ... you might not be unable to ring that bell this year ... but next year make it plain to them in some matter ahead of time that this Thanksgiving Day your plans are specific and that they are not part of them.
No need to be tactful. Say it like it is. Always the best way... say it once and you won't have to be tactful ever again.
Say NO exactly how you said it here.. It's that easy.
Suggest a different time they visit, and apologize that your guest list is already full.
Perhaps they're lonely? I have spent the last three Thanksgivings alone as well as Christmas. That's a horrible feeling. Maybe they're changed, humbled? Something to think about...
Lol. I can't repeat what I would say here.
but thanksgiving is about family i mean you cant that prude
Just tell them there are too many people coming over as it is