Many people find it hard to compare mobile plans. That's understandable: there are dozens of providers, hundreds of bundles, and a maze of terms and conditions. Which bundle fits your usage? Which network works well in your area? And what does '5G' actually mean in practice?
In this article, we explain what you really need to look out for when choosing a Sim Only plan, so you don't overpay and don't run into any surprises.
What exactly is Sim Only?
A Sim Only plan is a mobile plan without a phone. You use your own device and pay monthly only for calls, texts, and data. The big advantage? You're not tied to high device repayments and have more freedom to switch or adjust your bundle.
Ideal if you're happy with your current phone or if you buy a device yourself. Most Sim Only plans can be cancelled monthly, which is handy if your situation changes or you find a better deal.
The five most important selection criteria
1. Network coverage and speed
The quality of the network determines whether you can make calls without interruptions and whether your internet runs nice and fast. In the Netherlands, there are three network providers with their own infrastructure: KPN, Vodafone, and Odido. All other providers rent capacity on one of these three networks.
What to check:
- Coverage in your area: coverage can vary by provider and by region. Always check the provider's coverage map.
- Real-world speed: not every provider offers the same speed, even on the same network. Virtual providers may apply their own speed limit.
- 5G: 5G is now standard with all major providers as well as virtual providers. You do need a 5G-compatible device. The difference between providers lies in speed and network priority, not in 5G availability.
2. Bundle size: how much data do you need?
Too little data leads to high out-of-bundle costs. Too much is a waste of money. Check your current usage in your phone settings (iPhone: Settings > Cellular; Android: Settings > Network & internet > Data usage).
Rule of thumb:
- 1-3 GB: WhatsApp, email, occasional browsing. Suitable if you mainly use wifi.
- 5-10 GB: daily social media, YouTube, Google Maps. Sufficient for most people.
- 20+ GB: lots of streaming on the go, video calling, working from the cloud.
- Unlimited: you never want to think about usage. Note: some unlimited bundles have a fair-use policy. Check the provider's terms.
3. Customer service and availability
A low price is nice, but often means you sacrifice on service. Budget providers usually only offer chat or email, no phone helpdesk. Premium providers like KPN and Vodafone do have a phone number, but they're more expensive.
What to check:
- Trustpilot score: how do other customers rate the provider? Pay particular attention to recent reviews.
- Availability: can you call, or only chat? How quickly do you get a response?
- Self-service options: can you adjust your bundle yourself via an app or website?
For budget options, 50+Mobiel is a strong choice within our analysis: over 44,000 Trustpilot reviews with around 4.5 out of 5 stars. For full transparency: 50+Mobiel is co-owned by the Home of the Brave holding. We compare all providers using the same neutral criteria.
4. Price and temporary promotions
Don't just compare the monthly price, also look at what you get for it. Some providers offer temporary promotions such as double data in the first six months, or a discount when switching. Watch out for:
- Promotion terms: does the discount only apply in the first year? What do you pay afterwards?
- One-off costs: some providers charge connection fees or SIM card fees. Check this with the provider beforehand.
- Contract length: a 2-year contract is often cheaper, but a monthly cancellable plan offers more freedom.
Also read: Cheapest Sim Only plan: find the best deal
5. Extras: 5G, VoLTE, and roaming
All major providers as well as virtual providers now offer 5G as standard: faster internet with less delay. Handy if you stream a lot or work from the cloud. You do need a 5G-compatible device. With VoLTE (calling via 4G), you also get better call quality.
Also pay attention to roaming:
- Within the EU: you can usually call and use the internet without extra charges (EU roaming).
- Outside the EU: high rates often apply. Check the terms beforehand if you regularly travel abroad.
Switching to Sim Only: step-by-step plan
Step 1: Choose the right provider
Start by comparing providers. Pay attention to coverage quality, price, bundle size, and customer service. Torn between two options? Welli compares all providers in real time and shows you which bundle fits your usage.
Step 2: Request number porting
Want to keep your current number? Let the provider know when you sign up for your new plan. Your new provider takes care of the rest, you don't need to do anything with your old provider yourself.
Step 3: Activate on the switch date
Once your new SIM card arrives, you'll receive an activation date. On that day, your old plan automatically stops and the new one starts. Insert the SIM card into your phone and you're done.
Common mistakes when choosing Sim Only
Mistake 1: Choosing the wrong bundle size
Bundles that are too small lead to high out-of-bundle costs; rates vary by provider, so check this beforehand in the terms. Bundles that are too large are a waste of money. Check your current usage before choosing.
Mistake 2: Only looking at price
A cheap plan with poor coverage or slow customer service will ultimately cost you more frustration than it's worth. Weigh price against quality.
Mistake 3: Not checking contract length
A 2-year contract is often cheaper, but if your situation changes (moving house, different usage), you're locked in. Monthly cancellable plans offer more flexibility.
Mistake 4: Forgetting roaming
Within the EU, you can usually call and use the internet without extra costs. Outside the EU, different rates apply; check this beforehand if you travel regularly.
Budget vs. premium: what's the difference?
Budget providers (such as Simyo, Simpel, Youfone, 50+Mobiel) are cheaper but offer less service. Premium providers (KPN, Vodafone, Odido) are more expensive but have better customer service and often faster internet.
What suits you?
- Choose budget: if you can solve problems independently and mainly use wifi.
- Choose premium: if you're often on the go, value phone support, or use it for business purposes.
Who is Sim Only interesting for?
Sim Only suits you if:
- You're happy with your current phone
- You buy a device yourself (separate from your plan)
- You want flexibility: monthly cancellable or a short contract
- You want to save money: no device repayment means lower monthly costs
Not suitable if you want to finance a new phone through your plan. In that case, a plan with a device makes more sense.
Conclusion: What to look out for with Sim Only?
A Sim Only plan is ideal if you want more control over your costs and don't want to be tied to a device. But you'll only make the best choice if you look beyond just the price.
Pay attention to these five points:
- Network coverage: check the coverage map for your area
- Bundle size: check your current usage and choose accordingly
- Customer service: read reviews and check availability
- Contract length: weigh flexibility against price
- Extras: 5G, VoLTE, and roaming can make a difference
Don't feel like figuring it all out yourself? Welli helps you choose. Not the cheapest deal, but the best deal for you.