Generally, for a cocktail reception, your guests will be comfortable if you allocate half the amount or about 10 square feet per person.
Remember to add on whatever square footage your hired entertainers will need. A wacky wax or novelty photo set-up, for instance, usually calls for at least two mid-size tables, as well as room for the waiting line.
Also, be careful about factoring in only usable square footage. Don't let a party site include footage that's essentially useless for seating your guests, such as the lobby or a balcony area overlooking the main room (unless that's where you want some of your guests to eat!).
12’X12’ dance floor = 144 sq. feet = A guestlist of 100 (50% dancing)
12’X15’ dance floor = 180 sq. feet = A guestlist of 120
15’X15’ dance floor = 225 sq. feet = A guestlist of 144
15’X18’ dance floor = 270 sq. feet = A guestlist of 180
For a crowd that loves to dance, where you’ll have more than half the people on the floor at any one time, or to insure a nice wide Hora circle, alter your calculations. Assume that two-thirds of the party is always on the floor. For a typical Bar or Bat Mitzvah of 125 guests, this translates into 82.5 guests dancing at any one time (you get to decide which guest is the .5). Multiplied by 3 sf per person, you need 248 sf or a 15'X18' portable dance floor.
How many events will be held at the same time as mine? Most professional party planners agree it's much better to be the only event at your venue. Why? An overcrowded parking lot, a cookie-cutter feeling instead of one of importance and uniqueness, a possibly distracted venue staff, the possibility of noise and unpredictable behavior from the other events' guests. (You may already have enough unpredictable behavior from your own guests.) If the place you love is one that always has multiple events at the same time, find out what written policies the venue has to prevent some of these issues. Get any verbal assurances in writing.
Who handles plowing of snow from the streets, sidewalk and parking lot near the venue? If you're having a winter party, you want to make sure your guests, particularly the elderly and less spry, can easily access the space. Request the venue have a plan in place to clear all paths well before your start time. Put it in the contract.
If the party is being held at venue such as a synagogue or rental hall that's connected to a charitable organization, see if and when the space holds any kind of community outreach program. "I found out only by accident that our synagogue was planning on having the soup kitchen at the same time my party was going to start," says one New York mother. "And there's only one shared entrance. I didn't think it'd be appropriate so now I have to find another space." Her event is less than two months away.
Ask who, exactly, from the venue will remain at the event throughout your event. We say "throughout" because, at one recent B Mitzvah at a prestigious venue, the event manager and her assistant went AWOL halfway through the party. Important questions and upsetting snafus went unsolved -- much to the dismay of the host family. (The venue owner later tried to make amends by issuing a small refund.) So clarify any venue's policy on staffing its event. Then make sure it's spelled out -- down to the titles (such as "Building Manager," "Coat Check Operator") and specific hours -- and get it written into your contract.
