Style Guide
Dress Codes Decoded: Black Tie, Cocktail, Semi-Formal & Casual
Formal, cocktail, semi-formal, smart casual… event dress codes sound precise but they are often confusing. This is your at-a-glance reference for every common invitation — including what to wear and what to avoid — so you can RSVP with confidence.
Dress codes at a glance
- White tie: the most formal — a full ballgown, long gloves and an updo.
- Black tie: a floor-length evening gown in a luxe fabric with elegant heels.
- Black-tie optional / formal: a long gown or a very dressy midi.
- Cocktail: a knee-length or midi dress in a polished, dressy fabric.
- Semi-formal: a step below cocktail — a midi or polished knee-length dress.
- Smart casual: a relaxed dress, jumpsuit or separates with neat shoes.
- Casual: a sundress or comfortable everyday dress; denim is often acceptable.
Formal and black tie
Formal events — galas, balls, awards nights and formal weddings — call for a full-length gown. The more formal the wording, the longer and more elegant your dress should be. Floor-sweeping fabrics, defined waists and one statement detail are the recipe. Read our full black-tie guide or browse formal and red-carpet dresses.
Cocktail and semi-formal
Cocktail is the most versatile dress code. A knee-length or midi dress in lace, satin, scuba or a tailored fabric is perfect — dressier than office wear, but not as formal as a gown. Semi-formal is very similar but slightly more relaxed; a polished midi or a dressy knee-length dress is ideal. This is where elegant prints, an off-the-shoulder neckline and a great pair of heels shine.
Smart casual and casual
Smart casual means neat and considered but relaxed — a midi dress, a soft sundress, a jumpsuit or a dress with trainers or flats. Casual is the lowest-effort tier: a comfortable sundress, a relaxed T-shirt dress or a casual midi with sandals. For a casual wedding or a relaxed gathering, a floral midi or an easy maxi always looks pulled together. See our casual dress edit.
How to choose when you are unsure
When an invitation is vague, look at the venue and the time of day: evening, hotel or ballroom events are dressier; daytime, garden and home events are more relaxed. Match the most formal possible interpretation without going overboard — it is better to be slightly overdressed than underdressed. Let the season guide your colour and fabric, and always choose something you can comfortably sit and move in.
Shop by occasion
Every dress in our collection is tagged by the occasion it suits. Start with wedding guest dresses, date night outfits, evening gowns or vacation wear.
Frequently asked questions
Q.What is the most formal dress code?
White tie is the most formal, traditionally requiring a full ballgown, gloves and an updo. Black tie, which calls for a floor-length gown, is the most common formal code today.
Q.What is the difference between cocktail and semi-formal?
They are very similar. Cocktail calls for a knee-length or midi dress in a dressy fabric, while semi-formal is a touch more relaxed — a polished midi or dressy knee-length dress.
Q.What should I wear to a smart casual event?
A midi dress, a neat sundress or a jumpsuit with flats, sandals or low heels is perfect — relaxed but clearly considered.
Q.Is it better to be overdressed or underdressed?
Slightly overdressed is the safer choice. When the dress code is unclear, match the more formal reading based on the venue and time of day.
Q.What do I wear to a dressy daytime event?
A floral midi, an easy maxi or a polished knee-length dress in a lighter fabric and colour works for daytime weddings, garden parties and lunches.