Hmmm. Well as everyone has said it already barely any point in my adding it in but, basically, no.
I think there are lots of foolish myths that surround the notion that 'if you, the professional actor, become known for your extras work, you will become known to one and all as an extra, and never be taken seriously as a professional actor', which is, frankly, absolute rubbish...most extras are not actors, and I see no reason at all why an actor who has been known, on odd occasions, to do some extras work to help pay the rent should be dismissed by a casting director on that basis, if they are also known to have done plentiful amounts of well - respected mainstream acting work!
But that does beg the question. Basically, if all you can lay claim on your CV is extras work, then you are an extra, not an actor, and no Casting Director is going to fall for the pretence that you are an actor in a million years. But as we are all actors here, then really the point is just listing extras work is not going to impress anyone - it demands no actual skill at acting (as anyone who has ever done it will know), and even if it was done on the set of a big name film, it is quickly apparent that your contribution to that film would have been pretty negligible. I don't think that saying you were on the same set with Russell Crowe, for instance, cuts any ice with anyone unless they can determine that you actually had a line you spoke to him, or something similar.
Now, it's true to say that there is a hierarchy of 'background' work, and being 'featured' is slightly more viable acting work (sometimes it's a real performance demanded of you), and having a 'speaking role' (even if you didn't initially audition for one) is tantamount to being in the cast list. So, of course, this type of 'extras' work is certainly worth putting on the CV (but only because it's almost verging on having been cast in a role properly!) - I'd say a good rule of thumb might be - if you would consider that the section of the film you were in would be worth putting on a showreel- then stick it on the CV. So, even your part as a non - speaking ladies's maid who, nonetheless, hovers conspicuously in frame and performs certain tasks vital to the scene may warrant a mention on the CV - at the very least, a Casting Director will recognise that you made some 'performance' contribution to the finished product. If it's a shot of the back of your head, or a blink and I'd miss you panning shot across a crowded ballroom, or a standing gurning in a crowd moment, then frankly, I hope you took the money for it, and you're leaving it off the CV.
