The first time I flew into Taoyuan for a Taipei work week, I'd assumed I would buy a Chunghwa Telecom SIM at the airport. The Chunghwa counter required my passport and a Taiwanese registration step. The agent was helpful but the queue moved slowly during the post-flight peak and I lost forty minutes that I'd planned to spend on the airport-to-Taipei MRT figuring out the office's exact entrance. The next trip I bought a Taiwan eSIM at the Hong Kong layover and walked off the plane at Taoyuan with Chunghwa 5G already pre-loading the Google Maps walking directions from the MRT to the office.
Why buying an eSIM beats the airport kiosk
Chunghwa Telecom, Taiwan Mobile, FarEasTone, and Taiwan Star all operate prepaid counters at Taoyuan International, Kaohsiung International, and Taipei Songshan. A SIM is a real option for a longer stay, especially for digital nomads on multi-month rentals or for resident expats. But the counters require your passport and a Taiwanese registration step, and can be slow during peak Lunar New Year, summer-tourism, or business-week arrival banks. An eSIM installs from a QR code before you fly, activates on first Taiwanese tower contact, and skips the arrivals queue.
Most travellers into Taiwan fit one of three shapes: short Taipei-focused city visitors (4-7 days, night-market and museum focus); round-island travellers using the THSR (Taiwan High Speed Rail) or driving the coast (7-10 days, multi-region itineraries); and outdoor visitors for Taroko Gorge, Alishan, Sun Moon Lake, or the central mountain trekking routes (5-10 days, mixed-itinerary). All three want data from the gate onward.
What Chunghwa, Taiwan Mobile, FarEasTone, and Taiwan Star coverage actually looks like
Taipei has solid 5G across central districts (Xinyi, Da'an, Zhongshan, Wanhua, Songshan, Zhongzheng), the Taoyuan airport corridor, the Taoyuan Airport MRT, and the entire Taipei MRT network. Tunnel sections of the MRT have continuous 4G/5G via repeater systems. Kaohsiung has strong 5G across the central districts, the harbour, and the airport approach. Taichung, Tainan, Hsinchu, and Hualien all have widespread 5G in their commercial centres.
The Taiwan High Speed Rail (THSR) corridor between Taipei and Kaohsiung maintains continuous 4G/5G with brief tunnel drops. Conventional TRA rail (the round-island line) has continuous coverage at all settled points. The Taipei-Yilan, Taipei-Hualien, and Hualien-Taitung coastal routes all have strong 4G.
Tourist destinations have strong 4G. Sun Moon Lake (Nantou), Alishan, Kenting (the southern beach resort area), Jiufen (the historic mountain town), Beitou hot springs, and the National Palace Museum all have continuous coverage. Taroko Gorge has 4G at the entrance and visitor centre; deep gorge trails thin briefly.
The outer islands (Penghu, Kinmen, Matsu, Lanyu) have continuous 4G in their main towns and at major scenic points; outer beaches and ferry crossings thin briefly. The central mountain trekking routes (Yushan summit, Snow Mountain, Hehuanshan ridge) have variable coverage at altitude with some sections essentially offline.
Most travel eSIMs route through Chunghwa Telecom, which has the widest national footprint.
How the major eSIM providers compare in Taiwan
Pricing models vary across providers. Custom plans, where you set data amount and validity independently rather than picking from preset bundles, are 99esim's distinguishing feature and the only option in the tracked set for that level of flexibility. Airalo sells fixed bundles with the widest country list in the category. Holafly sells unlimited day-pass windows at premium Taiwan pricing. Nomad covers Taiwan on a fixed-bundle model. Ubigi prices Taiwan on the cheapest short-validity per-GB tier in the tracked set.
Taiwanese pricing sits inside the East Asian normal band. Ubigi's $3.00 / 1 GB / 7 day is the cheapest entry. Airalo's $4.00 / 1 GB / 3 day and Nomad's $4.00 / 1 GB / 7 day are next. 99esim's €3.99 / 1 GB / 7 day is competitive in EUR terms but slightly higher in USD-equivalent. Holafly's $12.90 / 3 day unlimited is the most expensive entry but the only unlimited option. The matrix below spells out the per-axis shape for Taiwan specifically. For a short Taiwan trip, Ubigi is the clear price-leader.
Install timing: when to set it up
Install the eSIM the night before you fly, or during a Hong Kong, Tokyo, Singapore, or Manila layover. The QR code generates immediately after payment; scan it with your phone's eSIM settings; the profile installs but doesn't activate until it first sees a Taiwanese tower. At the gate, switch your home SIM's data off and land at Taoyuan with data already working.
iOS 17.4+ devices can install directly from a provider's app without scanning a QR code, on providers that support it. Android users still scan a QR code, which takes thirty seconds.
Who should pick what
A 4-7 day Taipei-focused city visit works on a 1 GB / 7 day plan. Ubigi at $3.00 is the cheapest.
A 7-10 day round-island circuit (Taipei + Taichung + Tainan + Kaohsiung + Hualien) benefits from a 3-5 GB plan because THSR coordination, Google Maps navigation, and night-market food-tour use across multiple cities adds up.
A combined Taiwan + Japan or Taiwan + Hong Kong East Asian trip wants an Asia regional plan rather than two stacked country plans.
A heavy streamer or content creator posting daily night-market or temple-visit video without meter anxiety fits Holafly's unlimited-day model only if the premium Taiwan day rate is worth it.
A short two- or three-day Taipei business visit fits Ubigi's $3.00 starter or any provider's smallest tier.
A trekking visitor for Yushan, Snow Mountain, or central mountain ridges benefits from a 3 GB plan with the understanding that high-altitude sections will be partially offline.
A group of three or more travelling together, particularly a family round-island circuit or business delegation, benefits from 99esim's group eSIM, which covers up to four devices on one purchase. None of the tracked competitors offer that product today.
A note on Taiwan's mobile network density
Taiwan has one of the most consistently good mobile-network experiences for short visitors of any country. The combination of dense urban towers, strong rural coverage, MRT tunnel coverage, and aggressive 5G deployment means coverage gaps are rare in normal tourism patterns. Even the central mountain trekking routes have better coverage than equivalent altitudes in Switzerland or Japan. The practical implication for travel-eSIM choice is that any provider works well — the differentiator is price, validity flexibility, and per-trip economics rather than any meaningful coverage gap. For most short visits, Ubigi's $3.00 entry tier is the cleanest answer; for longer stays or multi-device groups, 99esim's custom plans and group-eSIM justify the modest premium.