When is the best time to visit Iceland?

For a first trip with a car, June to early September: every road is open, the highlands too, the days are endless, the weather is as kind as Iceland gets, and the puffins and whales are in. It is also the most expensive and the busiest, so book hotels and cars months ahead and expect company at the famous stops.

For the northern lights, late September to March: nights are dark, and the two equinox windows, September to October and February to March, have the most settled skies and the most active sky. For ice caves, mid-November to March. For the lowest prices and the quietest roads, November and January, which also have the least daylight.

If you want a taste of everything at a reasonable price, the shoulders win: September has lights, open roads and the autumn colours in the highlands until the roads close; late February and March have lights, ice caves, ten to twelve hours of daylight and the South Coast to yourself on a weekday.

Pick the thing that matters most and the month follows.

• Northern lights: September to March, best odds in September, October, February and March. Not possible May to mid-August.
• Ice caves (the blue ones under Vatnajökull): mid-November to March, guided only. Katla’s black ice cave runs all year.
• The highlands (Landmannalaugar, Þórsmörk, Askja): late June to early September, when the F-roads are open. Nothing else gets you there except a Superjeep tour.
• Midnight sun: late May to mid-July; the sky never goes dark from mid-May to early August.
• Puffins: mid-May to mid-August at Dyrhólaey, Látrabjarg, the Westman Islands and Borgarfjörður eystri.
• Whales: April to October, best June to August from Húsavík and Akureyri; humpbacks in Faxaflói from Reykjavík most of the year.
• The full Ring Road: June to September for the north and east passes to be reliably open; shoulder months with a spare day; not December to February on a fixed schedule.
• Lowest prices: November to February, about 20 percent under the shoulder months for hotels and cars; flights are cheapest in the same window outside Christmas.
• Fewest people: October to April outside Christmas and New Year, and anywhere beyond the South Coast in any month.
• Families: June to August for daylight and open pools; the Easter and October half-terms work for a short South Coast trip.

Daylight and darkness on the 15th from solar geometry, the cost of a week for a couple in comfort hotels from the budget model, and the F-roads usually open, for every month. Each month name links to its page.

Summer (June to August): 18 to 21 hours of daylight, 10 to 15°C on a good day, every road and most campsites open. The highlands open in late June and the first autumn storms arrive in the last week of August. Hotels and cars are at their most expensive and the Golden Circle and South Coast car parks are full from 10:00 to 16:00; start early and stay late.

Autumn (September to October): the best value in the year. Lights are back, the highlands hold on until the roads close in late September, the colours in Þórsmörk and around Mývatn are at their best in the second half of September, and prices fall after the first week. Storms grow through October; by the end of the month winter rules apply.

Winter (November to March): four to eleven hours of daylight depending on the month, storms that close passes for a day or two at a time, and the South Coast, the Golden Circle and Reykjavík as the practical range for a week. In return: ice caves, lights, snow on everything, empty car parks and the lowest prices. A 4x4 with winter tyres and a spare day in every five are not optional.

Spring (April to May): daylight comes back fast and the lights fade by mid-April. April is the most changeable month, with snow and sun in the same afternoon and the north still closed some days. May is quietly excellent: long days, lambs and birds, the Snæfellsnes and South Coast roads clear, prices still at shoulder level, and nothing busy before the last week.

Every month has a catch, and knowing it in advance is what makes the trip work.

• Wind, every month. Iceland’s weather is wind first and temperature second; a 25 m/s gale in July is as real as one in January. Plan for it and nothing surprises you.
• Summer crowds are concentrated: the same twenty stops between Reykjavík and the Glacier Lagoon between 10:00 and 16:00. The north, the east and the Westfjords are quiet even in August.
• Winter daylight is the constraint, not the cold. Five hours of light is two hours of driving and three places; a plan that ignores it ends on a pass in the dark.
• Prices move with the season for hotels and cars only; food, fuel and tours cost the same in January and July.
• Shoulder months are the ones that need a spare day. A September or March storm can close the Ring Road for 24 hours; with one free day in the plan it costs nothing.
• Cruise days: when a ship is in at Reykjavík, Akureyri or Ísafjörður the nearest sights are busy from 09:00 to 15:00 in summer; the port schedules are public.

If the list above has not settled it, answer these in order.

• Lights or highlands? Lights means late September to March; highlands means late June to early September. Neither means any month, and you are choosing on price and crowds.
• How much driving? A full Ring Road wants June to September; a South Coast and Golden Circle week works in any month with the right car; the Westfjords want June to August.
• Fixed dates or flexible? With school holidays you are in July, August, Easter or October half-term; book nine months out for summer. With flexible dates, late February to March and September are the sweet spots for value.