It is not uncommon to hear someone say “I agree” or “I concur”, seemingly interchangeably in fact. On the surface, the expressions seem possibly interchangeable as such – but are they really? Could it be that “agree” and “concur” are just another example of synonyms in the English language, or is there more to the story than what there may seem?
The reality is that both “agree” and “concur” can in fact be used interchangeably. You can say: “I agree”, or “I agree with you”. You can also say: “I concur”, or “I concur with you”. Literally all of these examples convey an identical message. So is there any difference in their use at all? Grammatically speaking, no. Popularity wise, however, possibly. I should seem that more people prefer saying “agree” and view “concur” as less informal. It also is less likely for the English speaker to include “with you” when simply using a verb fulfills its function in the sentence. For this reason, it is much less common to hear “I concur with you” than it is to hear “I agree”. Does that mean one should be used more than another? No, it just comes down to personal speech preferences.
It is true that many people view “concurrence” as more eloquent and less causal than “agreeing”. It may even be true that you’ll receive more strange looks if you use the former over the latter in casual conversation. However, the key is to remember that neither is more correct.