Playa Arenillas generally offers calm, protected waters suitable for swimming, particularly during the dry season (December to April). As a small beach within the sheltered Papagayo Peninsula, conditions tend to be gentler than exposed Pacific beaches. However, always check current conditions before entering the water, as occasional waves and currents can occur. There are no lifeguards on duty, so swim at your own discretion. The sandy bottom and typically clear waters make it relatively easy to assess depth and conditions.

The best time to visit Playa Arenillas is during the dry season, from December through April, when you'll find sunny skies and minimal rainfall. For fewer crowds, consider visiting on weekdays or during the shoulder months of November or early May. Early mornings and late afternoons offer the most serene atmosphere at this quieter beach. The green season (May to November) brings afternoon rains but also lush landscapes and even fewer visitors, making it ideal if you prioritize solitude over guaranteed sunshine.

Access to Playa Arenillas typically requires transportation through the Papagayo Peninsula area. Most visitors reach the beach via rental car or taxi from nearby towns like Playas del Coco or from Liberia airport, about 30-45 minutes away. Some areas of the peninsula are accessed through resort properties or gated developments, so confirm access rights beforehand. A 4x4 vehicle may be helpful during rainy season, though not always essential. The beach's quieter, local-resort character means signage may be limited, so GPS coordinates or detailed directions are recommended.

Playa Arenillas has limited on-beach facilities due to its quieter, local-resort character. Nearby accommodations range from vacation rentals to small boutique properties scattered around the Papagayo Peninsula. For dining, you'll likely need to travel to nearby beaches or resort restaurants, as beachfront options directly at Arenillas are sparse. The towns of Playas del Coco and Playa Hermosa, both within 15-20 minutes, offer more extensive restaurant and lodging choices. Many visitors pack snacks and drinks for their beach day here.

Playa Arenillas stands out for its low-key, intimate atmosphere compared to the larger, resort-dominated beaches on the Papagayo Peninsula. This small shoreline attracts fewer crowds and maintains a more local feel, making it ideal for couples seeking privacy and tranquility. Unlike the heavily developed beaches nearby, Arenillas offers a more authentic Costa Rican beach experience. The calm waters and scenic setting provide excellent conditions for relaxation and easy swimming without the commercial bustle of neighboring beaches.