OMG I did this very same stupid thing. Fortunately I was caught at my home airport because I was going to the UK! The lady said, "um, you can't go forward because your passport isn't signed," and I backed up and signed up, and all was well, and we all had a big laugh.
Originally Posted by
gelplanes
My US passport was issued more than a year ago. I've used it to travel overseas and return to the US more than 8 times, never a problem.
Then.... I arrived at LHR and was told that I would be refused entry. The border inspector wanted to know how I was able to travel so many times(he saw all the entry/exit stamps/visas) when my passport signature line was blank.
To be honest, I hadn't noticed it until now. I admit that it is my fault for signing it. However, I'm wondering if they can actually refuse me entry if I didn't sign my passport right there at the counter? I did sign it in front of the inspector and said
(edited to avoid confustion: I only said it in my mind 
) "there... you happy now?"
He let me in and told me not to forget to sign my next passport... (8 years from now, I guess)
