Many people may want to use an iPhone 15 but are concerned about the high price of a new device. While SoftBank offers discounts for contract bundles, buying a used device and using it with a SoftBank line is actually a shortcut to getting the smartphone environment you want while keeping costs down. This article will explain in detail the differences between a carrier bundle contract and purchasing a used device, their respective advantages and disadvantages, and how to safely choose a used device for those who want to use an iPhone 15 with SoftBank.

How to Use iPhone 15 with SoftBank | Comparing Two Options

Features of Purchasing iPhone 15 with the Device from SoftBank

With SoftBank, you can purchase an iPhone 15 series device and a line contract together. Bundle contracts often include campaigns like "Shin Toku Suru Support," trade-in programs, and long-term usage benefits, which can sometimes reduce the actual cost burden.

However, device payments can be spread out over a long period, up to 48 installments, creating a risk of high outstanding balances if you cancel mid-term. Additionally, it's important to note the numerous optional contracts and conditions tied to the plan. Users who prioritize smartphone freedom may find these restrictions somewhat binding.

How to Use a Used iPhone 15 with SoftBank

Purchasing a used device and signing up for a SIM-only contract with SoftBank is an effective way to significantly reduce initial costs. Especially with a SIM-free device, you have the flexibility to use it not only with SoftBank but also with other carriers or low-cost SIMs.

Furthermore, existing SoftBank customers can easily switch devices by simply swapping out their SIM card or reconfiguring their eSIM. This method is also appealing to those who want to change models at their own convenience without being tied to contract conditions.

View PRODIG's iPhone 15 Series Lineup

iPhone 15 Series | Differences and How to Choose Each Model

Differences Between iPhone 15 / 15 Plus / 15 Pro / 15 Pro Max

The iPhone 15 series consists of four models, allowing you to choose according to your purpose and lifestyle.

• iPhone 15: Standard size, characterized by lightness and balance

• iPhone 15 Plus: Large screen, suitable for watching videos and viewing documents

• iPhone 15 Pro: Lighter with titanium material, features ProRes recording and A17 Pro chip

• iPhone 15 Pro Max: All Pro features plus a 5x telephoto lens

The model you should choose depends on which features you prioritize. If you're particular about photo/video shooting, the Pro series is recommended. For everyday use, the standard 15 or Plus is a good choice.

Key Points for Choosing the Right iPhone 15 for You

The key points for choosing are "size, weight, processing performance, camera performance, and budget" (5 points). If you prioritize lightness and cost-effectiveness, the iPhone 15 is a good choice. For photo and video production, the iPhone 15 Pro or higher is ideal. If battery life is a concern, larger capacity models like the Plus or Pro Max are also options.

When buying used, checking the exterior condition and battery capacity allows you to choose a device that is practical while keeping costs down.

SoftBank's Pricing Plans and Compatibility with Used Devices

SoftBank's Main Pricing Plans and Overview

Here are some of the main plans available from SoftBank:

• Merihari Mugen +: For heavy users focused on video and social media (unlimited data)

• Mini Fit Plan +: Tiered pricing for light users

*Information as of June 2025. Please contact carrier shops for details.

These plans are also available for SIM-only contracts, making them highly compatible with used iPhones. Especially when combining a used device with a SIM-only plan, you can avoid unnecessary device costs and choose only the communication plan.

Differences Between Used Devices and Bundle Contracts / Pros and Cons

Bundle contracts include the device cost in the monthly payment, making them unsuitable for short-term model changes or early cancellations. On the other hand, using a used device offers greater freedom in contract terms and flexible replacement in case of device issues.

Even if it's not the latest model, an iPhone 15 with sufficient performance can provide reliable use at a balanced cost by choosing a good-condition used device.

Checkpoints When Purchasing a Used iPhone 15

Confirming if the device is SIM-free and why

When purchasing a used iPhone 15, it's crucial to choose a SIM-free device. If the SIM lock hasn't been removed, you won't be able to use it with carriers other than SoftBank, and your future options for switching carriers will also be limited.

By confirming in advance whether "SIM-free" is indicated or if the lock has been removed by the original seller, your freedom in choosing a carrier will significantly increase.

Exterior Ranking, Battery Remaining, Red SIM Warranty

When assessing the reliability of a used iPhone, the product's condition is crucial. PRODIG clearly displays the following information:

• Exterior rank (S to C)

• Maximum battery capacity (% display)

• Red SIM warranty (compensation if network usage restrictions occur)

With these in place, you can purchase a used device with peace of mind, even without seeing it in person.

Check PRODIG's peace of mind guarantee

Benefits of Purchasing an iPhone 15 at PRODIG

Points for secure purchase and customer support

At PRODIG, all used iPhones are shipped after being checked for operation and cleaned, with exterior rankings and battery information clearly indicated with photos. This allows even first-time used smartphone buyers to choose a product with confidence.

Furthermore, comprehensive after-sales support is provided, including handling issues after purchase and a red SIM warranty.

In-store (Akihabara) purchase and trade-in support

If you are concerned about online purchases, you can also visit our physical store in Akihabara for in-person purchases and consultations. We also offer trade-in services for your current device, reducing the hassle when upgrading.

Check PRODIG's trade-in service

Frequently Asked Questions & Q&A

Q. Can a used iPhone 15 be used with SoftBank?

A. Yes, it can be used without any problems if it's a SIM-free device. It supports SoftBank's nano-SIM and eSIM, allowing for a smooth device change from an existing contract.

Q. How do I differentiate between using a SIM card and an eSIM?

A. A nano-SIM is a physical card that you insert, while an eSIM allows you to switch network information within the device. The iPhone 15 supports both, and using an eSIM allows for multiple lines to be used simultaneously.

Q. What if I'm concerned about device warranty?

A. PRODIG offers products with a red SIM warranty, alleviating concerns about network restrictions. If you want to prepare for natural failures or physical damage, you might consider separate insurance or AppleCare.

Finally

For using an iPhone 15 with SoftBank, combining a used device purchase with a SIM contract is an excellent choice in terms of cost, flexibility, and reliability. Especially with PRODIG, you can not only choose a device in good condition with confidence but also receive comprehensive support, including after-sales service and in-store assistance.

If you want to avoid losing money on a device purchase and desire flexible smartphone usage, PRODIG's used iPhone 15 is an optimal choice for you.