With so many rules about what to wear to a wedding, an invite can have you completely confused.  You want to be respectful to the bride and groom, but you don't want to be overdressed.  Check the invitation to see if it states the formality.  If not, you may want to check with a bridesmaid or mother of the bride for the dress code.  The location and time of the wedding and reception may also give you a clue.  Evening weddings tend to be a bit more formal than their daytime counterparts.  Evening dresses are acceptable for just about any formality except a casual wedding.   

Wedding Attire Formality Deciphered 

White Tie:  This is the most formal affair of all.  Women will be expected to arrive in floor length evening gowns in neutral colors.  Dress pumps should be worn and accessories should be sophisticated.  Diamonds are perfect for this event.  Long white gloves are very acceptable as well.  

Black Tie:  This is also a very formal event.  Women may still want to choose a floor length evening gown, but, if desired, a cocktail length dress will work as well.  Jewelry should be as formal as for white tie, however, more jewel options are open for this type of a wedding.

Black Tie Suggested or Optional:  This is still considered a formal affair.  However, women can choose to wear an evening dress, a cocktail dress or a suit dress.  Color is not quite as important as with a white tie event, but you will still want to choose a darker palette. Jewelry doesn't need to be quite as fine, but still should not be too casual.  Something similar to mother of the bride dresses or bridesmaids dresses could work.  

Semi-Formal:  Still a step above casual, semi-formal leaves many options open.  Women can choose a long or short evening dress or even choose a skirt and blouse (for warmer weather) or skirt and sweater (for cooler weather).  

Casual:  If the wedding is in the evening, casual DOES NOT mean jeans and a t-shirt (unless the bride and groom have specified such). Women can wear dress pants or a skirt.  Most business casual type dresses would be acceptable as well.  Consider if the wedding is in the evening or daytime.  If it is a daytime wedding, sundresses might work.  

Some Points to Consider:  While rules have changed over time, most brides will still appreciate it if no female guests wear white.  Black, while once a taboo to wear to weddings, is now very acceptable for an evening affair.  Clutches are the best type of handbag for weddings. The formality of the wedding will determine the materials in the clutch - silk or satin for evening and more casual fabrics for daytime.  If the wedding ceremony is being held in a church or is religious, consider dressing a bit more modestly.  Keep shoulders and arms covered by wearing sleeves or by carrying a wrap.  

Check out the examples below to help you in your quest for your wedding attire.