500-word essays do not have to be exactly 500 words, but they should be as close as possible. The essay prompt may say "in under 500 words" or "at least 500 words," which would state whether 500 is the minimum or maximum word count. Generally, the more you can narrow down your argument, the better it will be; this means that breaking up your essay into subheads will help you to cover more ground in less time. Even if you don't think you'll be able to fit all you want to say in one piece, splitting it up might still be a good idea. As long as you follow the basic structure of a paper outline, you shouldn't have any problems writing a 500-word essay. You could probably even write longer ones if you wanted to! Of course, the quality of your work will suffer if you go beyond the allotted word limit, so keep that in mind when planning out your essay. It's very easy to write longer essays than necessary. If you find yourself thinking about something else while writing your paper, don't worry about it - you can always come back and add it in later. It won't cost you anything extra and it's better to be too thorough than not thorough enough. The most effective way of keeping your essay within the required length is by using subheads.