Keep Your Number on a Low-Cost Voice Plan, Get Data via eSIM | A Dual SIM Savings Guide

If you want to lower your monthly phone bill without changing your phone number, there's a simple approach: keep your number on a low-cost voice plan and use an affordable data-only eSIM for mobile data. This is called running a dual SIM setup. Your number stays exactly where it is. You just add a cost-efficient eSIM for the part that uses the most: data. You aren't cutting anything; you're adding something. Depending on how much you call and how much data you use, this can bring your costs down. This guide explains how it works, how to choose, how to set it up and what to watch out for, in plain and neutral terms.

Prices, data allowances and plan terms can change. Wherever this guide gives figures or examples, please check each provider's official website for the latest details. Bloomy prices are shown in USD at checkout, so please check the current price when you buy.

What is dual SIM? Cutting costs without changing your number

Dual SIM means using two SIMs (two lines) at the same time on one smartphone. For example, you can keep calls and SMS on the line with your current number and use a separate, cheaper line for mobile data. Each line has its own job.

With this setup, you can move your data usage to a different line without canceling or porting your phone number. Your number stays active, so contacts from family and work, as well as SMS verification codes, keep working as before. If fear of losing your number has kept you from switching, this is a low-risk way to review your plan.

To see which combinations your phone supports, start with our eSIM-compatible device checker.

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Why "voice plan + data eSIM" often costs less (splitting the roles)

Your phone bill has two main parts: the base fee for calls and SMS, and the cost of data. For most people, data is where the price differences are biggest. A dual SIM setup splits the roles like this:

• Calls and SMS verification: a low-cost voice plan focused on keeping your number (the cheapest plan that keeps your number active)
• Mobile data: a cost-efficient data-only eSIM (choose only the amount you need)

The key point is that your number stays with your current carrier. You don't cancel anything or lose anything. You just add a line for data, so every service tied to your number keeps working. If your voice plan includes a little data too, it can serve as a backup if the eSIM line ever has a temporary problem.

To compare data options across plans, see our comparison articles and our guides to saving on your phone bill.

How to choose a low-cost voice plan for keeping your number

For the calls and SMS line, the top priority is keeping your number active at a low cost. There are two broad approaches:

• Lowest cost: very cheap or near-zero base-fee plans. These may come with conditions, such as needing to top up or use the line regularly, and if you forget, your number could expire.
• Low effort, more peace of mind: a small fixed monthly fee. Your number stays active even if you never think about it.

Plans differ a lot by country and carrier, so it helps to compare them on the same points. The table below lists what to check. For actual prices and terms, look at your carrier's official website.

What to check	Why it matters	Tips
Monthly base fee	This is what keeping your number costs you each month	Ask your carrier whether it has a lower-tier or "number-keeping" plan
Conditions to keep the number active	Some low-cost or prepaid plans expire if you don't top up or use them	Check the expiry rules and set a reminder if needed
Call rates	If you make a lot of calls, per-minute charges add up	Compare per-minute rates or optional call add-ons with how you actually use your phone
SMS support	You need it for verification codes from banks and other services	Make sure the plan can receive SMS
Included data	A little data can act as a backup line	Very slow speeds may only be good enough for messaging
Setup fees and contract terms	One-time fees or early termination charges affect your real savings	Check for minimum terms and switching fees

Lowest cost or peace of mind?

The cheapest number-keeping plans often require regular top-ups or activity, and your number could lapse if you forget. Fixed-fee plans cost a little more but carry no risk of forgetting. Neither choice is right for everyone. It comes down to whether you'd take a bit of extra effort for the lowest price, or pay slightly more to avoid the hassle. For more on phone numbers and SMS, see our phone number and SMS articles.

Add data with an eSIM | Bloomy data plans

For data, a data-only eSIM where you choose just the amount you need is easy to manage. One important point: Bloomy is a data-only service. It does not come with a phone number, SMS or voice calls. That's why this setup depends on keeping your number on a separate voice plan (with your current carrier). Calls and messages through apps such as WhatsApp may work whenever you have a data connection.

Examples of plan sizes (available plans and coverage vary by destination, so please check the details and the current USD price at purchase):

Data	Validity	Price
1GB	7 days	Check at purchase
3GB	30 days	Check at purchase
10GB	30 days	Check at purchase
20GB	30 days	Check at purchase
50GB	30 days	Check at purchase

To find a plan by data amount and validity period, use our eSIM comparison page.

Estimating your savings by combination

So what will you actually pay? A simple way to estimate is to add your two costs together and compare the total with your current bill. These are illustrative patterns only. Your real numbers depend on your current contract and usage, so check each provider's official website for current pricing. This setup does not guarantee savings.

Combination (example)	How to estimate your monthly total	Good for
Number on a fixed-fee low-cost voice plan + Bloomy 20GB data	Voice plan fee + data plan price	People who want to keep their number with no hassle and use a moderate amount of data
Number on the cheapest voice plan (calls and verification only) + Bloomy 10GB data	Voice plan fee + data plan price	People who use the number line only for calls and SMS codes

When you compare with other all-in-one plans, compare them at the same data amount and under similar conditions to see the real difference. Plug in your own usage and pick a data amount on our comparison page.

Setting it up | How to use dual SIM

It may sound complicated, but the steps are simple. Keep your number (voice SIM) as it is, add a data eSIM, and assign each line its role.

1. Keep your current voice SIM active (don't cancel it).
2. Add a data eSIM. Install it using the QR code or instructions you receive after purchase.
3. In your phone's cellular settings, assign the roles: "voice = voice SIM" and "mobile data = eSIM".
4. If needed, follow your device's instructions, such as turning on data roaming for the eSIM.

After that, calls and SMS use your existing number, and internet traffic uses the eSIM. Steps and screens vary by device, so follow along with our setup guide. If you have trouble connecting, see our FAQ.

Check device and SIM compatibility first

There are a few ways to set up dual SIM, and support varies by device.

• Physical SIM + eSIM: If your current number is on a physical SIM, adding a data eSIM is the simplest option.
• eSIM + eSIM: Some devices, such as iPhone 13 and later, can keep two eSIMs active at once.

Before you buy, check whether your device supports eSIM and which combinations it allows. Our eSIM-compatible device checker can help. It's also worth confirming that your phone is carrier-unlocked.

Drawbacks and things to know

Here are the downsides as well as the benefits, so you can decide with the full picture.

• Bloomy is data-only. It does not include a phone number, SMS or voice calls, so keep your number and SMS verification on your voice plan.
• Very cheap or near-zero plans can take effort to maintain and may let your number lapse. If the plan needs regular top-ups or activity and you forget, you could lose your number. If you'd rather not keep track, a fixed-fee plan may suit you better.
• You'll manage two lines (two bills, two data balances). It takes a little extra effort at first.
• Speed and reliability depend on the local network, your device, your coverage area and congestion. Please keep in mind that fast speeds aren't available everywhere at all times.
• If you're considering an unlimited-style plan, it may come with a fair use policy, slower speeds after a certain amount of use, or tethering restrictions. Check the latest terms before you buy.

With these points in mind, knowing you can keep your number and pay less only for data makes reviewing your phone bill much easier.

Summary | Keep your number, add data instead

A dual SIM setup is a low-risk way to cut your phone bill: your number stays the same, and an affordable eSIM handles the data. For your number, choose between the lowest-cost plan (which may need occasional upkeep) and a hassle-free fixed-fee plan. For data, add only as much as you need through an eSIM. That's the basic split. Start by checking your device's compatibility and how much data you use each month.

Next steps: check your device, find a data plan that fits your usage and timeframe on the comparison page, and read through the setup guide so you're ready to go.