Planning wedding reception, how to estimate size room to book before you know how many guests will attend?

We booked a room that accommodates 120 people max on the assumption that many relatives from across the country would not be able to attend. Turns out many of them are actually coming, and we've run out of space at the reception. How could we have planned this better? Book a larger room to play it safe? But... show more We booked a room that accommodates 120 people max on the assumption that many relatives from across the country would not be able to attend. Turns out many of them are actually coming, and we've run out of space at the reception. How could we have planned this better? Book a larger room to play it safe? But then you're committing to extra expense that may not be necessary...
13 answers 13