Google suggest a limit of around 50k keywords per account. With your campaign I would sugest you look at the relevncy of each keyword, if it is possible to group them into themes and divide them into AdGroups with relevant adverts your Click through rate, Quality Score and conversion rate should all improve
Hey The only limit on number of keywords is really RELEVANCY. If you deem 1000 keywords to be relevant to what you are promoting then include them. However, that is highly unlikely from experience. I tend to keep my ad groups small - 25 or 30 keywords maximum - and have many of them. That way my campaigns remain relevant from keyword -> ad group -> ad copy -> landing page. Cheers Stewart
Standard accounts Google adgroup keyword limit is 2,000 keywords Google Account keyword limit is 50,000 Level 1 upgrade account keyword limit is 100,000 Level 2 upgrade account keyword limit is 500,000 Level 3 upgrade account keyword limit is 1,000,000