The average campaign yard sign is about two feet wide and a foot and a half tall. The type of sign that you purchase is a contributing to the standard size of a sign. In general, fold over or cardboard lawn signs will be slightly wider than plastic bag for corrugated plastic yard signs since they need some extra width to staple down around the wire frame.
Campaign Trail Yard Signs carries the common sizes for each type of sign in addition to some larger signs if you are trying to stand out from the crowd or have a long time or office title:
Plastic Bag Signs
26″ Wide x 16″ High
32″ Wide x 20″ High
36″ Wide x 14″ High
20″ Wide x 14″ High
Corrugated Plastic Signs
24″ Wide x 18″ High
Cardboard Signs
22″wide x 14″high
28″wide x 11″high
28″wide x 22″high
44″wide x 14″high
While larger signs particularly are going to stand out from the crowd of other signs, the traditional sizes are more economical. Another financial factor to signs are the number of colors to use on the sign. Check out the product page to see how varying the sign type, color, and size impacts the price, so you get both the features that you need at a price the campaign can afford.