A memorial service may induce sadness and mourning, but it is a time to pay respects to and celebrate the life lived by the deceased. You want to show respect for the bereaved and the deceased as well as demonstrate how you've been affected by the loss. Your memorial service attire should generally be low-key and unassuming, keeping the focus on the needs of the bereaved.
Clean and Presentable
Memorial services are typically less formal than funerals and thus it is often not strictly necessary to wear your Sunday best. However, your clothes should always be clean, pressed and presentable. Don't wear jeans or socks with holes. Avoid T-shirts with inappropriate sayings or ultra-casual footwear, such as flip-flops. Don't wear dirty or muddy shoes to the service. Never wear clothes that are too tight or too loose. Your clothes are part of your overall statement of respect -- don't embarrass yourself or other mourners with clothes that draw negative attention.
Some memorial services feature a clothing theme. Survivors of the deceased may ask guests to wear a shirt in the deceased's favourite colour. If the deceased worked in fashion, guests may be encouraged to wear the deceased's favourite style or brand. Check before dressing for the memorial service to ensure you are complying with all themes and wishes of the deceased. Even if you don't feel festive, a memorial service clothing theme is just another way to honour the deceased.
If the memorial service is held in your city, you likely know what kind of attire is acceptable. For out-of-town services, however, check with the organisers about local customs regarding dress. Some cities may consider it disrespectful for women to wear a dress above the knee or for men to arrive without a tie. If the deceased was from a different culture or adhered to a different religion, ask about a dress code well in advance. If you are a woman attending an Orthodox Judaism service, for example, you may be required to cover your head before attending.
When in doubt, dress up. You can't go wrong with formal attire that clearly shows you've made a respectful effort to look your best. For women, this means a dark-coloured or earth-tone suit or dress with heels. In more conservative settings, dark stockings are also a safe bet. Men should wear a dark suit with a tie and dress shoes. If you are overdressed at the memorial service, you may stand out but not in a negative way.