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April 23, 2014

Why you need the right SIM card in your Nokia smartphone

As we all know, most smartphone technology zips along at a cracking pace. However, there are some very important parts of the package, which evolve a little more sedately. Put your hands together for the humble SIM card.

The first SIM card was produced way back in 1991 and while it’s form has changed its function is more or less the same. It’s perhaps for this reason that people sometimes underestimate the problems they can create by using adapters or by cutting SIMs into shape. Happily, help is at hand to ensure you don’t fall into that trap. Our man at Nokia Care, Wayne Spillet, has put together this handy guide for anyone unsure about why messing with your SIM is bad for your Nokia smartphone. Over to you, Wayne.

It can’t have escaped many people’s attention that we currently have three different types of SIM card in use, and it can be confusing for some to know which one we need for our particular phone. SIM stands for Subscriber Identity Module, and in total, there are four types:


(1) SIM: this is the size of a credit card and has been obsolete in mobile phones for more than a decade, but even today when we get a new SIM, chances are we will need to pop it out of a credit card-sized piece.

(2) Mini-SIM: This is the main type of SIM card that we have known for a number of years and fits the largest number of phones currently in use globally.

(3) Micro-SIM: This is now beginning to overtake the Mini-SIM as the most commonly used in new phones, including Nokia Lumia and X phones plus some of the latest Asha models.

(4) Nano-SIM: This type of SIM is the smallest yet, not used in many phones but already a feature in the Nokia range for users of the Lumia 1520.

There are many people cutting SIMs down to size to make them fit into some phones, while others are using adapters to make smaller SIMs fit into larger slots. Nokia always recommends that you use the correct type of SIM card, and here is why:

For many years, SIM cards sat under a metal gate in the battery compartment of a phone; or slid under a metal bridge, also inside the phone (see above), in which case it is very easy to ensure that the SIM card is correctly positioned on the contacts. Today, however, as manufacturers work on miniaturisation to make our phones slimmer, many phones have SIM cards which slide into a small slot on the side of the phone, either in a special tray (see below) or in the same way that we insert our Micro-SD memory cards.

Why not cut a Mini-SIM to fit a Micro-SIM slot?

Traditional Mini-SIM cards are slightly thicker than modern Micro- and Nano-SIMs, and so there is sometimes the risk that the cut SIM could damage the contacts on the phone’s SIM card reader. Many network operators today supply SIM cards with two pop-out sections so that the user can choose when they receive their new SIM whether to have Mini- or Micro-SIM; in these cases the whole card will be the same thickness as a Micro-SIM, so you do not have any risk, but you should NOT cut a standard Mini-SIM for phone designed to take a Micro-SIM. There is a secondary risk with cut SIMs, and this is that the cutting process can in some cases damage the metal chip and so render the SIM card useless.


Why not us adapters to use an adapter to fit a smaller SIM into a larger slot?

If an adapter is used to insert a Nano-SIM into a Micro-slot or a Micro-SIM into a Mini-slot, there is the risk that the SIM card may be loose inside the adapter, in which case it can move during insertion and damage the SIM card contacts in the phone; or in some cases that the adapter assembly itself could be thicker than the SIM , which also may damage the contacts during insertion.


Whether you have an affordable Asha, an exciting X or a lovely Lumia, we appreciate that you chose a Nokia phone and we know that it is a valuable investment that you need to use every day, and we would hate a quick shortcut concerning your old SIM card to cause damage to your phone and leave you out of touch with your family, friends and business contacts. That’s why Nokia always recommends the use of the correct type of SIM card for your phone.

Nokia Care