Your Travel Companion, Built by Travelers
eSIM connectivity in 200+ destinations, with no SIM swapping and no roaming bills — built by a team that lives the problem.
co:sim is a global travel eSIM. Buy a plan before you fly, install it in under a minute, and it activates the moment you land — no swapping cards, no restarting your phone, no surprise roaming bills. One account holds every eSIM you've ever bought from us, ready to top up or re-use.
Our Story
By travelers, for travelers.
$120 for a week of roaming in Italy. A 40-minute queue for a Thai SIM card at 11pm, after a 14-hour flight. A "free" hotel WiFi in Lisbon that asks for your room number and forgets it five minutes later. We have paid those bills, stood in those queues, sworn at those captive portals. That is why we built co:sim.
Built with Silicon Valley DNA: pragmatic, infrastructure-first, allergic to friction. Asia-focused from day one — where mobile-first travellers and the steepest roaming bills collide.
We are not the biggest eSIM brand. We aim to be the one you actually want to use again — no surprise charges, no app maze, no fake 'instant chat' that turns into a 12-hour ticket queue. Just a connection that works the moment your plane lands.
co:sim launches.
Industry-first AI Agent API — ChatGPT, Claude, and friends can buy on your behalf.
200+ destinations · 8 languages · live in your pocket.
What We Believe
Mission
Make global connectivity feel as natural as opening a map app — instant, affordable, invisible. We measure ourselves by the friction we remove, not the features we ship.
Vision
Be the default eSIM for anyone who crosses a border — for a weekend, a quarter, or a way of life. The companion you forget is even there, because it just works.
Purpose
Return the joy to travel. Every bug we fix, every checkout we shorten, every support reply we send is one less reason for a traveller to feel lost the moment they land.
Why co:sim
AI agent ready
Open API + llms.txt so ChatGPT, Claude and friends can buy on your behalf.
See how to connectWide coverage
200+ destinations on a single profile.
30-day self-service refund
Uninstalled? Get a refund without a ticket.
Install before you fly
Auto-activates the moment you land.
Pay how you like
Card, Apple Pay, Google Pay, Alipay, WeChat, Amazon Pay.
Real-human support
Live chat staffed by people, not just bots.
Built on the Road
Our team works from the same cafés, co-working spaces, and airport lounges where you'll use co:sim. We test the product in the wild — these are a few of our favourite places to log in from.
Tacos and TypeScript.
Spring all year round.
Where it all clicked.
Rice fields and deploys.
Sunsets and standups.
Where focus meets fun.
Our team is our customer. Every bug, every feature, every late-night fix happens in a co-working space, an airport lounge, or a beach café. That is why we know what a good eSIM is worth — and why we have no patience for a bad one.
Built for the AI Era
You already use AI for hotels, flights, and itineraries. Why not connectivity too? Our open API lets ChatGPT, Claude, Gemini, Manus, OpenClaw, Hermes — and whatever ships next — find, compare, and buy your eSIM. With an agent payment tool like AgentCard, it can even pay. Change your mind? 30-day self-service refund, no questions.
You are helping me buy a travel eSIM through co:sim (https://cosim.io). First, fetch and read https://cosim.io/llms.txt and https://cosim.io/openapi.yaml — they tell you every endpoint, the request shape, and the auth model. Use those, not URLs in this prompt. Then, for the trip I describe below, please: 1. Recommend a co:sim plan that fits. 2. Show me the total cost in USD and the data allowance. 3. Create a checkout link and give me the URL to pay. My trip: - Destination(s): <country or region> - Travel dates: <start date> to <end date> - Expected data use: <light / normal / heavy> - Email for the eSIM delivery: <your email> Please reply to me in English.