Know-How Exchange : Career/Training

Marketing Manager generally sounds larger/more impressive to me than Marketing Communications Manager. In my experience, MarCom Managers would report to Marketing Managers.

You can also look up the positions on Salary.com to determine which one is closest to your actual job description. While it's a big help to your career to get to determine your own title, you also want to be accurate in case you want to search for other work later. If you list yourself as the Marketing Manager and your next potential employer determines you were more of a Marketing Communications Manager, this could have a negative impact on their desire to hire you (they also may not care).

You also might consider a dual title if it becomes prudent. When I worked as the director communications for a small nonprofit, my title had to later be changed to "Communications and Creative Director" (or more officially, but cumbersome, "Director of Communications and Creative Director") as a new HR consultant strove for more accuracy in our position titles. (I was gunning for Communications and Creative Czar, but she didn't go for it.)

It benefits the company, as well. If you later leave, as I did, they need to advertise the position correctly to get the best candidates possible.

I'd troll around Salary.com and see which title(s) suit your actual role best.

All the best!