Spring and summer (May–September) is the best time to visit. June and July are the peak of summer: average temperatures around 20°C, and the long northern evenings — it stays light until 10pm or later in midsummer — make outdoor life very pleasant. The old town fills with visitors in summer but not unpleasantly so; it's a large old town and absorbs crowds well.
Autumn (October–November) brings cooler temperatures and the changing colour of the trees in Vingis Park and the Vilnia valley. October is still pleasant for walking; November turns grey and wet.
Winter (December–February) is cold, dark, and occasionally beautiful. The old town looks its best under snow, and the Christmas market in Cathedral Square and Vokiečių Street runs through December. Temperatures can drop to -15°C or below in January. Most tourist sites remain open through winter.
Events worth timing a trip around:
- Kaziukas Fair (first weekend of March, around St. Casimir's Day, March 4) — a traditional folk crafts market filling the old town streets with amber, linen, woven goods, and food. One of the most charming folk events in the Baltics.
- Vilnius Festival (June) — classical music concerts at Cathedral Square, the Congress Concert Hall, and other venues across the city.
- Vilnius Marathon (September) — the main annual road race, using a scenic course through the old town and river parks.
- Užupis Independence Day (April 1) — the self-declared republic celebrates its independence with street parties and the symbolic border post issuing entry stamps.