The best time to go to Nettuno is during the late spring (May to June) and early autumn (September to October) when the weather is pleasant for exploring and the crowds are smaller.
During May and June, the temperatures are comfortably warm, typically ranging from 20°C to 25°C, which is ideal for walking around the historic centre and enjoying the beaches without the intense heat of mid-summer. The sea is also warm enough for swimming towards late June. This period offers a good balance for those looking to enjoy both the town and the coast.
September and October also provide excellent conditions. The summer heat begins to subside, with temperatures averaging between 20°C and 26°C, and the sea remains warm enough for a dip. The main summer holidaymakers have departed, meaning you'll find fewer people at attractions and restaurants, and accommodation prices can be more favourable. This is great for travellers who prefer a more relaxed trip.
For those planning a beach-focused holiday, July and August offer the warmest sea temperatures and guaranteed sunshine, often exceeding 30°C. However, these months are also the busiest, with many Italian families on holiday, leading to crowded beaches and higher prices. If you don't mind the bustling atmosphere and heat, it's still a good time for a classic seaside getaway.