Updated September 28, 2026 · NomadCue Editorial Team
KKday vs WorldSIM
KKday
Higher score in this comparison
WorldSIM
KKday vs WorldSIM: the differences
| Compare | KKdayReviewVisitVisit | WorldSIMReviewVisitVisit |
|---|---|---|
| Price from | $0.80 | £25 |
| Price per GB from | $1.29 | £1.18 |
| Unlimited data | YesHas it | No |
| Reference plan prices | JP 10GB/30d $15.83; JP 15GB/30d $19.32; JP from 192 JPY; US/CA/MX 1-30d plans; EU 41-country 1-30d plans | Global eSIM Pro 10GB 30 days GBP 25; 20GB 90 days GBP 35; 41GB 180 days GBP 50; 85GB 365 days GBP 100; 10GB 30-day plan covers Europe, US, Japan, Thailand, Turkey and Mexico within 195+ countries |
| Fair use policy | daily allowance then throttled speeds | Fair and reasonable use only; WorldSIM may review charges or suspend or terminate the service if usage exceeds the terms of the agreement |
| Seller type | Marketplace | Mvno |
| 10 GB in Japan | $15.83 | £25 |
| Countries covered | Not confirmed | 195 |
| Networks | Not confirmed | AT&T, Rogers, Bell, Telus, Iusacell, Etisalat |
| Top-ups | Not confirmed | Yes |
| 10 GB in Europe | Not confirmed | £25 |
| 10 GB in the US | Not confirmed | £25 |
Same on both: 5G (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. Partners with a live offer in your country come first, then every other brand by score.
Key differences
- KKday scores higher overall: 8.9 vs 8.8.
- Unlimited data: only KKday.
- Support channels: only WorldSIM offers Chat.
- Founded is lower at WorldSIM: 2006 vs 2014.
- Region: only KKday offers Local, Regional.
- Features: only KKday offers Unlimited data.
- Audience: only WorldSIM offers Long trip.
Our verdict on each
KKday
KKday suits short-trip travellers who want flights, hotels, car rental, rail passes, tours and connectivity booked side by side. Plans start at $0.80, and Japan data runs from $1.29 per GB, so the site earns its place for a short trip assembled in a single checkout.
WorldSIM
WorldSIM is a UK MVNO eSIM built for travellers crossing several countries, where a global plan reaches 195 countries on established mobile networks. Plans start at £25, and 5G with instant activation make it a practical pick for multi-country trips rather than a bargain option.
Score breakdown
| Area | KKday | WorldSIM |
|---|---|---|
| Cost | Not confirmed | 8.4Entry pricing of £25 and £1.18 a GB sits above the medians €5 and €1.50. |
| Offer | 9.1 | 9.1Coverage of 195 countries, 5G, instant activation and top-ups. |
| Trust | 8.4 | 8.8Higher |
Choosing between them
Pick KKday if unlimited data matter most.
Pick WorldSIM if trust matter most.
Where they rank in our lists
| Ranking | KKday | WorldSIM |
|---|---|---|
| Travel SIMs and eSIMs | 31 of 926 | 32 of 926 |
| Travel eSIMs | 31 of 918 | 32 of 918 |
| Pocket WiFi rental | 4 of 193 | 5 of 193 |
Sources behind this comparison
KKday
- kkday.com: 6 facts, checked September 26, 2026
- ozbargain.com.au: 3 facts, checked September 26, 2026
- en.wikipedia.org: 2 facts, checked September 26, 2026
- linkedin.com: 2 facts, checked September 26, 2026
- livejapan.com: 2 facts, checked September 26, 2026
WorldSIM
- worldsim.com: 20 facts, checked September 26, 2026
Every fact side by side
| Fact | KKday | WorldSIM |
|---|---|---|
| Region | Local, Regional, GlobalCovers more | Global |
| Features | Unlimited data, 5G, Instant activationCovers more | 5G, Instant activation |
| Pricing model | Marketplace | Not confirmed |
| Audience | Short trip | Short trip, Long tripCovers more |
| Legal entity | KKday Holdings Co., Ltd. | WorldSIM Limited |
| Headquarters | Taiwan | United Kingdom |
| Founded | 2014 | 2006Lower |
| Support channels | Email, Help centre | Chat, Email, Help centreCovers more |
Pocket Wi-Fi
| Fact | KKday | WorldSIM |
|---|---|---|
| Deposit | Not confirmed | £0 |
| Data allowance | Not confirmed | 3.6GB |
| Devices connected | Not confirmed | 10 |
| Pickup and delivery | Not confirmed | Worldwide delivery, free over GBP 100 |
Where each stands against the rest
| Fact | KKday | WorldSIM | Median |
|---|---|---|---|
| Countries covered | Not confirmed | 195highest quarter | 120 |
| 10 GB in Europe | Not confirmed | £25highest quarter | £15.99 |
Median across 492 listed travel providers.
Pros and cons
KKday
Pros
- Sells flights, car rental and hotels alongside connectivity plans, so a trip can be arranged without moving between separate booking sites.
- Connectivity starts at $0.80, Japan data runs from $1.29 per GB, and a Japan data plan with a fixed volume is priced at $15.83.
- Plans fall under local, regional and global coverage, and reference plan prices cover Japan, the United States, Canada and Mexico as well as a Europe bundle.
Cons
- Unlimited data carries a fair use condition: daily allowance then throttled speeds.
- KKday is a marketplace, so the network behind a plan can differ from one listing to the next.
- Support is limited to email and help centre, without a phone line or live chat.
WorldSIM
Pros
- Coverage of 195 countries on a single global eSIM
- 5G and instant activation, so a plan works soon after landing
- Top-ups let you add data mid-trip without buying a new eSIM
Cons
- Unlimited data is not offered, so every plan runs on a fixed allowance such as 3.6GB
- Support runs on chat, email and help centre only, with no phone line listed
- The fair use policy lets WorldSIM review charges or suspend or terminate the service if usage goes beyond the terms of the agreement
Who each suits
KKday
Who it suits
- Short-trip travellers who want an eSIM or pocket WiFi in the same basket as flights, hotels and tours.
- Travellers heading to Japan, the United States, Canada, Mexico or a multi-country Europe trip, based on the published reference plan prices.
- Shoppers who are comfortable on a marketplace, where the seller changes from plan to plan.
Who should look elsewhere
- Travellers who need only bus tickets: FlixBus is built around bus.
- Anyone whose trip is mostly a rental car and an airport transfer: Hertz Bahamas WiFi focuses on car rental and transfers.
- Readers after the broadest product list: MoMo also covers flights, rail and bus, adding rail and bus to the mix.
WorldSIM
Who it suits
- Travellers crossing several countries on a single itinerary
- Long-stay travellers buying larger data blocks with longer validities
- People who want a UK-based MVNO with top-up flexibility
Who should look elsewhere
- Buyers after the lowest entry price, who may prefer eSIMGo.is from $0.99
- Travellers who want the widest country list, who may prefer Zwitchy at 200 countries
- Travellers who need data in a single country, where SimToIsrael from $25 is a closer match
Current offers
WorldSIM
Current offer
Bonus
Get your eSIM FREE and up to 25% bonus credit with selected airtime purchases: 25% bonus credit
Selected airtime purchases; eSIM cost free on the GBP 60 and GBP 125 airtime tiers
Source, checked September 26, 2026
Questions about each
KKday
What does a KKday plan cost?+
Connectivity starts at $0.80, and Japan data runs from $1.29 per GB. A Japan plan with a set data volume is listed at $15.83, with a larger volume priced slightly above it. Reference prices also cover North America and a Europe bundle.
Is the data unlimited, and what are the limits?+
Unlimited data is offered, and the fair use note is the catch: daily allowance then throttled speeds. Unlimited data and instant activation both appear in unlimited data, 5g and instant activation, so heavy users on a fixed daily cap should read the terms closely.
WorldSIM
How much does a WorldSIM eSIM cost?+
Plans start at £25, and the cheapest data works out at £1.18 a GB. The Global eSIM Pro range steps up in both data and validity, so a larger block lowers the cost per GB over a longer trip.
How many countries does a WorldSIM eSIM cover?+
A plan reaches 195 countries, and the networks behind it include AT&T, Rogers and Bell. Regional and global plans draw on established carriers, so a single eSIM can carry you across a whole itinerary.