Best eSIM for San Juan in 2026
— Ranked by Real Performance

San Juan operates on a US-territory network framework, meaning LTE and 5G coverage quality is broadly comparable to the mainland US — T-Mobile, AT&T, and Claro Puerto Rico share the dominant infrastructure, with T-Mobile holding the deepest 5G footprint after its post-Maria network rebuild investment. This makes it a strong destination for data-dependent travellers: digital nomads, cruise stopover visitors, and business travellers will all find reliable speeds in the metro area. The non-obvious detail most providers won't tell you: Claro Puerto Rico, a subsidiary of América Móvil, anchors the majority of budget MVNO eSIM routing on the island — not T-Mobile or AT&T — which is why real-world speeds from cheaper eSIM plans can lag behind what the US-territory branding implies.

• →T-Mobile Puerto Rico operates the island's most extensive 5G NR (New Radio) network, covering Old San Juan, Condado, Isla Verde, and Santurce — but 5G access via eSIM depends entirely on which wholesale agreement your provider has negotiated, and most consumer eSIMs default to LTE-only Claro PR routing.
• →Claro Puerto Rico's LTE network delivers average download speeds of 18–28 Mbps in urban San Juan — functional for streaming and video calls, but noticeably slower than the 80–120 Mbps median achievable on T-Mobile 5G for providers with that access tier.
• →Puerto Rico is a US territory with no roaming charges for US travellers, but international visitors still require a local or US-routable eSIM — the island is not covered by standard 'Americas' regional eSIM plans that exclude US territories, a common gotcha that catches European travellers off guard.
• →Indoor coverage in the older colonial architecture of Old San Juan (thick masonry walls, narrow streets) creates predictable signal attenuation — providers routing via T-Mobile's 600 MHz Band 71 low-frequency spectrum maintain significantly better indoor penetration than those limited to Claro's 1900 MHz AWS bands.