What to wear to a destination wedding as a guest.

Wear what the dress code on the invitation or the couple's wedding website asks for, then adjust the fabric and the shoes to the place. The Knot's dress code guide gives the example: black tie in tropical Tulum and black tie in the snowy Colorado mountains are different outfits.

When no code is named, three clues settle it.

• The invitation and the hour. The Emily Post Institute calls the invitation and the time of the wedding the best guide to its formality. An evening wedding tends to be dressier than a midday one.
• The venue. A resort or club is likely to ask for more than a ceremony on the sand, and a castle for more again.
• The couple. Ask them. If you are still unsure, dress up, not down.

A named code such as black tie or beach formal has its own rules, set out in the wedding dress code guide.

A destination wedding guest needs three outfits: one for the welcome dinner, one for the wedding day and one for the farewell brunch. The timings below are from an example Friday-to-Sunday programme; the couple's own schedule is the one to follow.

The destination wedding packing list for guests has the rest.

Destination wedding guest attire follows the ground and the weather: linen or cotton in the heat, a thick heel or a flat on sand and grass, and a layer for after sunset. The table follows The Knot's guest attire guides.

Check the hour the wedding ends as well as the hour it starts: a short dress that suits a hot afternoon can leave you cold after sunset.

What you wear to a destination wedding in Mexico depends on the coast and the month, but at a beach resort it is beach or resort attire in linen or cotton: a maxi or midi dress with dressy flat sandals or block heels, or a linen suit or shirt with loafers, tie optional. If the invitation says tropical formal, see tropical formal attire.

Hurricane season runs from 1 June to 30 November on the Caribbean side and from 15 May to 30 November on the Pacific side, according to the US National Hurricane Center, so plan for rain in those months. For a church ceremony, cover your shoulders or bring a shawl.

Men wear a suit in a summer fabric such as linen or seersucker to a formal warm-weather destination wedding, in blue or tan in place of black, with a tie unless the invitation says otherwise. That is The Knot's reading of beach formal. Below that level:

• Beach cocktail. A long-sleeved button-down shirt, dress trousers and a blazer or sport coat, with loafers. The tie is optional.
• Beach casual. Chinos with a button-down shirt (short sleeves are fine) or a plain polo. Skip shorts unless you know they are welcome.

Black tie still means a tuxedo: the Emily Post Institute lists it as required when the invitation states black tie.

Do not wear white unless the couple ask for it, a formal gown on a beach, or thin heels on sand or grass.

• White. A white shirt under a suit is fine, and so is a print with a little white in it. An outfit that is mainly white is not.
• Thin heels. Stilettos and kitten heels sink into sand and grass. Wear a block heel, a wedge or a dressy flat.
• Beachwear. The Knot says flip-flops and denim are usually wrong even for a beach casual code.
• Strapless in wind. On a breezy waterfront, The Knot suggests something with more support.

A destination wedding guest can expect more than one event: the weekend may include a welcome dinner on arrival day, the wedding the day after and a farewell brunch on the last morning. The invitation and the wedding website carry the real schedule and say which events you are invited to. An example:

• Friday. You fly in and take a shuttle or private transfer to the hotel. The welcome dinner is at the venue or a nearby restaurant the couple has booked out.
• Saturday. The morning is free. Guests start getting ready around 14.00 for a ceremony timed to sunset, then a cocktail hour, the reception and dancing.
• Sunday. The farewell brunch runs about three hours. Some guests fly home that day and others stay one more night.

Before you accept, price the flights and the room and check your time off. Ask the couple about room booking deadlines and transport between events.

A destination wedding costs a guest an estimated $1,500 to $4,500 for a three-night trip. That planning figure is per person, in US dollars and all-in: the five lines priced below, plus extras the table does not price. It does not separate hotel taxes or resort fees, so check whether a quoted room rate includes them.

The five lines total less than the planning range, which also allows for unpriced extras such as costs particular to the wedding party (hair and makeup, a bachelor or bachelorette party, alterations). Airport transfers are not priced either. Plan with the higher range, and budget 15% above your own subtotal for unexpected costs.

Mexico from the US east coast is estimated at $1,500 to $2,500, and the Maldives from New York at $3,500 to $5,500, past the top of the range. Price your own route with the guest travel cost estimator.

Book the flight first, then the room, starting with the hotel block the couple has arranged. Guests pay for their own flights and rooms: the destination wedding etiquette guide covers who pays for what, and the wedding gift guide covers how much to give.

These mistakes cost a couple money or goodwill.

• Do not reply late. The couple cannot finalise catering, seating or transfers until they know.
• Do not bring a plus-one who was not invited. Head counts are paid for.
• Do not skip the welcome dinner to go sightseeing. It is part of the programme. If you have a strong reason to miss the dinner or the brunch, tell the couple ahead of time.
• Do not post photos during the ceremony if the couple has asked for an unplugged one.
• Do not drink so much on Friday that you lose Saturday.