Updated September 30, 2026 · TariffCue Editorial Team
co:sim vs Simbye
Where co:sim and Simbye differ
| Compare |  co:sim |  Simbye |
|---|---|---|
| Seller type | Mvno | Reseller |
| Host network | local carrier networks | NTT Docomo, KDDI/au, SoftBank, Rakuten Mobile (Japan); Orange Holiday Europe (Europe); 700+ partner networks worldwide |
| Price from | $0.99 | €1.95 |
| Reference plan prices | Global (117 areas) unlimited daily data: $13.99, unlimited daily data, no contract, 1-365 days; Global (117 areas) 20GB 30 days: $135.99, 20GB total data, no contract; cheapest plan overall: single-destination Data Only eSIM from $0.99, data varies, no contract (no 12-month or 30GB+ plans listed) | Japan 1 GB: EUR 1.95, 1 GB, 7 days, prepaid no contract (cheapest plan overall) | Japan Unlimited: EUR 18.95, unlimited, 7 days, prepaid no contract (cheapest unlimited) | Build Your Own eSIM, app only: 5-50 GB, 30-365 days validity, up to 10 countries (12-month, 30 GB+ line, price set in app) |
| Unlimited plan price | $13.99 | €18.95 |
| Roaming countries | 200 to 240Higher | 190 |
| EU roaming | Not confirmed | Included |
| Data rollover | Not confirmed | No |
| Markets | Not confirmed | CH, GB, PL, TR, US |
Same on both: SIM-only (Yes), 5G (Yes), eSIM (Yes), Hotspot sharing (Yes).
We earn a commission when you sign up through links on this site. Partner status can affect where a brand appears in our rankings.
Key differences
- co:sim scores higher overall: 9.4 vs 8.8.
- Roaming countries is higher at co:sim: 200 to 240 vs 190.
- Support channels: only co:sim offers Phone, Help centre.
Our verdict on each
co:sim
co:sim suits travellers who want a prepaid eSIM with wide reach and a low starting price, and plans open at $0.99. It is a data-only setup, so the eSIM, hotspot sharing and sim only options suit people who manage their own data rather than expect a handset with the plan.
Simbye
Simbye is a prepaid eSIM reseller that suits travellers who want a short single-market data plan instead of a long mobile contract. Its entry plan starts at €1.95, Japan eSIMs run on the major Japanese carriers, and help arrives by chat and email.
Score breakdown
| Area | co:sim | Simbye |
|---|---|---|
| Cost | 9.5HigherEntry pricing leads the set: $0.99 to open a plan and $13.99 for unlimited daily data, with no contract on either. | 8.7The entry plan is €1.95 and the unlimited plan is €18.95, with EU roaming included across 190 countries. |
| Offer | 9.2HigherWide reach with everyday extras: 200 to 240 countries covered, eSIM delivery, hotspot sharing and sim only plans, all prepaid. | 8.9Entry plan starts at €1.95, close to KnowRoaming at $1.75, while unlimited sits higher at €18.95. |
Positions in our rankings
| Ranking | co:sim | Simbye |
|---|---|---|
| Phone plans with eSIM | 12 of 389 | 3 of 389 |
Where each is licensed and available
| Country | co:sim | Simbye |
|---|---|---|
| Headquarters | United States | United Kingdom |
If neither fits
eSIMony has roaming countries at 300, against 200 to 240 for co:sim and 190 for Simbye.
eSIMony reviewSources behind this comparison
co:sim
- cosim.io: 14 facts, checked September 30, 2026
Simbye
- simbye.com: 18 facts, checked September 30, 2026
Every fact side by side
| Fact | co:sim | Simbye |
|---|---|---|
| Billing | Prepaid | Prepaid |
| Contract length | Not confirmed | 1, 12 |
| Legal entity | Comsand Inc. | Simbye Ltd |
| Headquarters | United States | United Kingdom |
| Support channels | Email, Chat, Phone, Help centreCovers more | Chat, Email |
Where each stands against the rest
| Fact | co:sim | Simbye | Median |
|---|---|---|---|
| Roaming countries | 200 to 240highest quarter | 190highest quarter | 100 |
Median across 176 listed providers.
Pros and cons
co:sim
Pros
- Entry at $0.99 puts co:sim at the front of the price ranking: 1 of 15.
- Reach of 200 to 240 countries with hotspot sharing, so one data plan can carry a phone and a laptop across a long route.
- Sim only eSIMs on prepaid billing, so nothing is locked into a contract before the trip: prepaid.
Cons
- Billing is prepaid only, so a long trip has to be bought and paid for up front rather than spread over a contract.
- Unlimited daily data costs $13.99 against an entry price of $0.99, so wide-area cover for a long route sits well above the figure a plan list opens with.
- Of the email, chat and phone on offer, phone is the least common: 18.8% of the listings here include it, against 93.8% for the help centre.
Simbye
Pros
- The entry Japan plan starts at €1.95, close to KnowRoaming at $1.75.
- Roaming reaches 190 countries and EU roaming is included, so a multi-country trip needs no extra regional pack.
- Japan eSIMs ride NTT Docomo, KDDI/au, SoftBank and Rakuten Mobile, with hotspot sharing available on the same plans.
Cons
- Data rollover is not offered, so an unused allowance expires with the plan it was bought for.
- Support runs on chat and email, with no phone line among the listed channels, so a failed install has no voice route.
- Simbye is a reseller, and the carrier you connect to in Japan belongs to a partner rather than to Simbye itself.
Who each suits
co:sim
Who it suits
- Travellers crossing several countries who want a prepaid eSIM and hotspot sharing.
- People who plan their own data and pay as they go, since billing is prepaid with no contract attached.
- Anyone with an eSIM-ready handset who wants a sim only plan.
Who should look elsewhere
- Travellers after a named local partner in a single country, such as a Japan trip, where BambooSIM runs on Local partner networks, e.g. KDDI (au) and SoftBank in Japan.
- Shoppers who prefer a reseller setup, since ESIMZON is reseller and KnowRoaming is reseller.
- Buyers who want a monthly contract to renew: billing is prepaid, and the listed plans carry no contract.
Simbye
Who it suits
- Travellers landing in Japan who want data on a major Japanese carrier without taking a handset contract.
- People who want to buy and install an eSIM in the app before departure.
- Readers who want a small prepaid top-up for a single market rather than a monthly allowance.
Who should look elsewhere
- co:sim suits anyone who would rather buy from an MVNO, as co:sim is mvno, than from a reseller working on partner networks.
- KnowRoaming fits a reader whose budget is set in dollars, with an entry price of $1.75.
- ESIMZON suits anyone who wants its named partner set, from AT&T and T-Mobile to Verizon, rather than a Japanese carrier mix.
Current offers
co:sim
Current offer
Bonus
Free 1 GB eSIM for new customers: 1GB free eSIM valid 7 days at $0
New customers only, one per person; applied automatically at checkout, no code; sign-in with email and a valid payment card required for verification, nothing charged; 42 territories (one EU-33 roaming card plus 9 single-destination cards)
Source, checked September 30, 2026
Questions about each
co:sim
How much does a co:sim plan start at?+
The entry price is $0.99, and it belongs to a single-destination data-only eSIM rather than a wide-area plan. That makes it the figure that appears first in a plan list, but it is not the cost of staying online across a whole trip. Budget from the unlimited price for multi-country use.
How much is unlimited data on co:sim?+
Unlimited daily data costs $13.99. That plan covers a wide area list and runs without a contract, and it is the line most readers set against other sellers' unlimited plans. The gap between this figure and the entry price is the trade-off: unlimited removes the need to choose a data amount and moves the budget up.
Simbye
What does the cheapest Simbye plan cost?+
The entry Japan plan starts at €1.95 as a prepaid plan with no contract, so you buy a set amount of data for a fixed trip rather than a monthly allowance. Unlimited data on the same Japanese coverage comes from the Japan Unlimited plan at €18.95. A Build Your Own eSIM can also be set in the app across several markets.
Is there an unlimited data option and what does it cost?+
The Japan Unlimited plan costs €18.95 and carries uncapped data for a short validity window, on 5G networks with hotspot sharing available. Compared with the entry plan at €1.95, the jump is large, so unlimited makes sense for a stretch of heavy use in Japan and less sense for a brief visit.