The Epilogue is the last chapter of Harry Potter and the Deathly Hallows. It shows an episode when Harry's children and Ron's children meet on a railway station to board the Hogwarts Express.

The very first sentence of the epilogue says the Epilogue happens on the 1st of September. But what year is it?

I know this should be easy to tell, because the book says “Nineteen years later” and we know all the dates, but I've computed it three times already and always got a different answer. So now I'm confused and think it's better to clear this up once and for ever, so that if other people are confused about the dates too, they can just find this answers here.