What is an eSIM?

The term “eSIM” has become part of many mobile users vocabulary in recent years - you might have seen it while browsing for a new phone handset or in advertisements from telecom companies.

SIM cards (short for “Subscriber Identity Module”) have been an essential component of phones and other mobile devices since their launch in 1991. These small PVC cards provide the device with a unique identity, which in turn allows it to connect to a mobile network, send messages and make and receive phone calls.

Over the last few years, however, more and more providers have been seeking to augment or even replace traditional SIM card technology with eSIMs. In an increasingly globalised society, the need to connect to multiple networks or easily switch between different roaming plans is fast becoming a priority for many smartphone users.

First developed in 2012, eSIMs are an answer to the limitations of the now 30-year old SIM card technology. In essence, they are a microchip that can store multiple different SIM card profiles on a single device, negating the need to physically switch cards when different services or network providers are required. This is often needed when travelling between countries or switching between private and work phone numbers, for example.

What then, are eSIMs? And should you be using one?

Their potential for eSIM use in consumer electronics is a relatively recent development - but one that has rapidly gained traction. As of 2024, major phone manufacturers like Apple, Nokia and Samsung include eSIM hardware as standard on many of their new models.

The first eSIM-enabled iPhones appeared in 2018. The same year, Apple added eSIMs to their cellular Apple Watch and data-enabled iPad models. They would later dispense with physical SIM cards altogether in the eSIM-only version of the iPhone 14.

Planning a trip away? Frequent travellers, tourists and those with family overseas clearly stand to benefit from the new technology - the tedious process of switching between multiple physical SIMs is replaced by an entirely digital process. Travel eSIMs, like those from BetterRoaming, allow easy switching of mobile network across borders to avoid international roaming fees. With eSIMs, adding or removing a roaming plan is as easy as scanning a QR code. The latest iPhone model can store up to 8 different eSIMs - a major testament to the telecommunication industry’s commitment to this new technology.

Of course, it’s not only individual customers who can benefit from an eSIM - organisations and companies, from small businesses to major corporations, are adopting eSIM usage wholesale. Why supply your employees with work phones, when you could simply download a new work number to their existing eSIMs? Why carry around two devices and two chargers when you only need one? This instant functionality also allows businesses to program and reprogram multiple devices at once, saving time and money across the board.

It’s not just functionality that has caused this market shift - while considerably smaller than the credit-card sized SIMs of the early 90s, today's plastic SIM cards continue to take an environmental toll. Their relatively complex construction of PVC, silicon and even gold makes them unsuitable for home recycling, while their environmental impact only increases when you factor in the larger plastic card holder that new SIM cards are housed in.

While physical SIM cards are often still a necessary component of smartphones, eSIMs negate the need for users to own multiple plastic SIM cards, drastically reducing the material usage of the mobile phone industry. Much like the banking industry’s gradual shift from physical bank cards to digital payments, eSIMs are seen as the logical next step in the product cycle. As the climate crisis accelerates, telecommunications brands are investing in achieving a greater level of sustainability, with eSIMs playing a key role.

Already in widespread usage, eSIMs definitely have a bright future.