Magusto Chestnut Planner for St Martin’s Day

How many chestnuts per person?

For a magusto with other food on the table, allow 250 g of raw chestnuts per person. That is the middle of the 200–300 g range idealista recommends, and it matches the Teleculinária recipe, where 1 kg serves 4. If the chestnuts are just a snack or starter, 125 g per person is enough (Ruralea gets 8 servings from 1 kg). We couldn't find any published guide for a magusto where chestnuts are the whole meal, so the planner's 375 g per person for that option is our own estimate.

The planner rounds your shopping up to the next half kilo, since that's how chestnuts are sold, loose or in bags, at Portuguese markets and supermarkets.

Example: a magusto for 10 people, with other food

10 people × 250 g = 2.5 kg of chestnuts
Medium chestnuts (about 80 per kilo): 2.5 × 80 ≈ 200 chestnuts
For roasting: 2.5 × 100 g = 250 g of coarse salt (sal grosso)

Large, medium or small chestnuts

Size changes how many chestnuts you get, not how much to buy. Portuguese grading counts fruits per kilo: in the classes used by UTAD (the University of Trás-os-Montes e Alto Douro), large chestnuts run 61–70 per kilo, medium 71–90 and small 91–110. The planner uses 65, 80 and 100. A street seller's dúzia (dozen) of medium chestnuts weighs about 150 g.

How to prepare them

Pick good ones. Look for a shiny shell and chestnuts that feel firm and heavy for their size, with no holes or mould. Drop them in water and throw away any that float.
Score every chestnut. A shallow cut through the shell, lengthwise or as a cross, lets the steam out, so they don't burst and are easier to peel.
Soaking is optional. Some Portuguese recipes soak them in hot salted water for 10–30 minutes first to loosen the shell. Others roast them straight away.
Coarse salt, on top or underneath. About 100 g per kilo, sprinkled over the chestnuts or spread as a bed on the tray or pan.
Wrap them in a cloth. Straight after cooking, cover them with a tea towel for 5–10 minutes (or roll them in newspaper, the traditional way) and peel them while still warm.

Times and temperatures by method

Portuguese recipes don't all agree, so these are ranges. They're done when the cut opens, the shell lifts away and the inside is soft: taste one.

Conventional oven: 200 °C, 20–40 min
Fan oven: 180 °C, 25–30 min
Air fryer: 200 °C, 10–20 min, in a single layer
Frying pan or pot with a lid: medium heat, 20–25 min
Clay roaster over embers: 15–25 min (rough guide)
Microwave: full power, 2–3 min per 6–8 chestnuts
Boiled with fennel seeds: 20–30 min in boiling water, then 10 min in the water

For boiled chestnuts (castanhas cozidas), Ruralea uses 1 litre of water, 1 tablespoon of coarse salt and 1 tablespoon of fennel seeds (erva-doce) for every kilo.

St Martin's Day and the magusto

São Martinho is always on 11 November; in 2026 it falls on a Wednesday. The legend says Martin, a Roman soldier, met a poor man shivering on a cold, stormy day and cut his cloak in two with his sword to share it. The clouds parted and the sun came out. That's where the Verão de São Martinho comes from: the spell of milder, sunnier days that often arrives around this date. It doesn't happen every year, so check the IPMA forecast if you're planning an outdoor magusto.

A magusto brings family and friends together over roasted chestnuts, traditionally around a bonfire (if you light one, follow the local rules on fires). In the Minho there's music and dancing, in Trás-os-Montes some villages boil chestnuts in big copper cauldrons, and in the Alentejo you may hear it called a castanhada. Schools and town councils across Portugal hold their own magustos in the days around 11 November. When you hear street sellers calling «quentes e boas!» ("hot and good!"), chestnut season has started.

11 November isn't a national public holiday in Portugal, but it is a municipal holiday in some areas, such as Penafiel and Alijó. Check with your câmara municipal if you're not sure.

Storing raw chestnuts

Somewhere cool, dry and airy, they keep for about a week. In the fridge, in a bag with holes, about a month. You can also freeze them in their shells for up to three months. Ideally, buy them a day or two before your magusto.

Frequently asked questions

How many chestnuts per person for a magusto?

Allow 200–300 g of raw chestnuts per person when there is other food. The planner uses 250 g, which makes 2.5 kg for 10 people. For a snack, 125 g per person is enough.

How long do you roast chestnuts in the oven?

In a conventional oven at 200 °C, 20–40 minutes; in a fan oven at 180 °C, about 25–30 minutes. Shake the tray halfway and start checking at 20 minutes.

How do you cook chestnuts in an air fryer?

Score each chestnut, preheat the air fryer to 200 °C and cook them in a single layer, cut side up, for 10–20 minutes. Shake the basket halfway.

Why do chestnuts explode?

Steam builds up inside the shell. Always score each chestnut before cooking, especially in the microwave.

When is São Martinho in Portugal?

Every year on 11 November. In 2026 it falls on a Wednesday. It is not a national public holiday, but some municipalities, such as Penafiel and Alijó, have their local holiday that day.

What is a magusto?

A Portuguese autumn gathering where chestnuts are roasted, traditionally over a fire, around All Saints and St Martin’s Day (1 and 11 November).