<p>Typically (for most schools), is it better to send in the required 3 letters or include an extra one? I've been looking around online and it doesn't appear to be much more of a benefit to include an extra letter. The school websites also doesn't say anything about extra letters.</p>
<p>I’m running into this problem too. A lot of the schools to which I am applying have online applications which have slots for only 3 letters. </p>
<p>On the other hand, one of the schools to which I am applying allows up to 5, and I will be taking advantage of that. If you have 4 strong letters, and the app process doesn’t explicitly deny or discourage sending more than 3, then I would ago ahead and send the 4th.</p>