Do you know that you don’t need to open a new account if need a new number. Just add it to your current family plan or convert to a shared plan. So, how much is to add a line on AT&T? It’s cheap. Only $9.99 for each additional line. And you are not required to add any extra features like text messaging or email/web. And the best part is of course all the lines in this AT&T family plan share the minutes. Well, you might be worried that you won’t have enough plan, right? Relax, all lines still get unlimited nights and weekends. And you know what, mobile to mobile minutes never count toward the monthly limit. One more perks here – any unused minutes can be rolled over to the next month. Now you know how much to add a line to AT&T, it’s time to start saving money by adding a new line.