Galaxy S9 SIM card guide

In almost all regions, you still need a physic SIM card in Galaxy S9 0r S9+ to make calls or use mobile data connections.

Galaxy S9 SIM card guide will help you understand everything about using a SIM card in Galaxy S9 and S9+

The guide will cover the correct size of Galaxy S9 SIM card, how to use the two slots in Galaxy SIM card tray, insert or change SIM card for Galaxy S9 and S9+, change mobile network settings in Galaxy S9 and S9+, and check mobile network connection and signal strength in Galaxy S9 and S9+.

Some questions related to using Galaxy SIM card are also answered.

What is the correct size of Galaxy S9 SIM card?

Galaxy S9 and Galaxy S9 and S9+ use nano-SIM cards, which is the smallest SIM card you can get from your phone company.

So, if you migrated to Galaxy S9 or S9+ from any of the following phones, you can use the existing SIM card for Galaxy S9 and S9+:

• Samsung Galaxy S6, S7 and S8 and all their variants (e.g., S8+, S7 edge, S6 edge and S6 edge+).
• Samsung Galaxy Note 5 and Note 8.
• Any of Samsung Galaxy A series: Galaxy A3, A5, A7, A8 and A9.
• Galaxy J3 2017 and later, Galaxy J5 2017 and later, Galaxy J7 and later.
• iPhone 5, 6, 7, 8 and X (and all variants).
• Moto X (all generations).
• Pixel and Pixel XL (all generations).
• LG G5, G6 (all variants), V10, V20 and V30.
• many others phones released after 2016

If you are not sure whether your existing SIM card can be used in Galaxy S9 and S9+, please post your question in the comments box below.

We will check it for you.

You MUST use the correct size of Galaxy S9 SIM card because the slot in the Galaxy S9 SIM card tray can only hold nano-SIM cards.

In theory, there are four possible sizes of SIM cards:

1. Full-sizeSIM (1FF). Full-size SIM is  “giant” in size: 85.60 mm × 53.98 mm × 0.76 mm. No Android phones used it.
2. Mini-SIM (2FF). Mini-SIM usually is now often referred as “big” or “normal”  or “standard” SIM card in some countries. Most carriers and phone manufacturers phased out mini-SIM a few years ago.  Very few Android phones in the market now use this big SIM card.
3. Micro-SIM (3FF). Micro SIM is the most popular size of SIM card for middle-range and entry-level Android phones. In some regions, micro-SIM is referred as “small” SIM card.
4. Nano-SIM (4FF). Nano-SIM is the smallest SIM card available for a smartphone today. Most flagship smartphones require nano-SIM.

In most regions, most carriers offer 3-in-1 SIM cards. You can detach it as a mini-SIM card first. A micro-SIM card can be detached from this mini-SIM card. In a sequence, you can then get a nano-SIM card from the micro-SIM card.

You can trim a mini-SIM to a micro-SIM card very easily because the metal part is not touched in this process.

But you may damage the SIM card if you try to trim a micro-SIM card to a nano-SIM card. For an old micro-SIM card, the metal plated part may need to be trimmed when you try to convert it to a nano-SIM card.

Therefore, it is not recommended to trim a nano-SIM card by yourself for Galaxy S9 and S9+. If you cannot use the existing SIM card in Galaxy S9 or S9+, you should try to get the nano-SIM card from your carrier.

How to use the two slots in Galaxy S9 SIM card tray?

In the USA and a few other regions,  Samsung only offers the single-SIM version Galaxy S9 and S9+. You are allowed to use only one SIM card in Galaxy S9 or S9+.

In most of the international markets, you can get the dual-SIM version of Galaxy S9 and S9+. So, you can use up to two SIM cards in one Galaxy S9 or S9+.

Although Galaxy S9 SIM card tray in the single-SIM and dual-SIM version looks similar, the slot 2 is slightly different and therefore the usage of the slot 2 of Galaxy S9 SIM card tray can be different.

For the single-SIM version Galaxy S9 or S9+, the nano-SIM card must be placed in slot 1.

The slot 2 can be either empty or occupied by a micro SD card as shown below. You cannot put a SIM card in slot 2.

However, for dual-SIM Galaxy S9 and S9+, you have more options:

1. A nano-SIM card in slot 1, another nano-SIM card in slot 2 (option 1 in the following illustration);
2. A nano-SIM card in slot 1, a micro SD card in slot 2 (option 2 in the following illustration);
3. A nano-SIM card in slot 1, empty slot 2;
4. Empty slot 1, a nano-SIM card in slot 2.

So, the difference is that the slot 2 in dual SIM version Galaxy S9/S9+ can be used for either a SIM card or a micro SD card (but not both at the same time); while the slot 2 in single-SIM version Galaxy S9 and S9+ can only be used for a micro SD card.

For both versions, slot 1 can be used for a nano-SIM card only.

How to insert or remove SIM card to Galaxy S9 and S9+?

You may follow these steps (marked in the animation below) to insert, replace or remove SIM card in Galaxy S9 and S9+.

Step 0: Power off Galaxy S9/S9+

Although it is not required, it is recommended to power off Galaxy S9 or S9+ before adding or changing the SIM card.

Step 1: eject Galaxy S9  SIM card tray

You need to insert the ejection pin (you can find it in the Galaxy S9 box) to the hole of Galaxy S9 SIM card tray (see Galaxy S9 and S9+ layout) as shown in the animation below.

You may apply some force so that Galaxy S9 SIM card tray can be ejected.

Step 2: Pull out of  Galaxy S9 SIM card tray

Once the SIM card tray is ejected, you can pull it out from the phone.

Step 3: Place the SIM card into Galaxy S9 SIM card tray

For the single-SIM version Galaxy S9 or S9+, you need to put the SIM card into slot 1.

For the dual-SIM version, you can put the SIM card into either slot. You can also put two SIM cards into the two slots.

Of course, if you want to use a micro SD card, you can put the SIM card into slot 1 only.

When placing the SIM card, you need to make sure:

• The metal (gold-plated) part is facing downwards (away from the screen when Galaxy S9 SIM card tray is placed in the phone).
• The notch in the SIM card matches the slot.

Placing the SIM card in a wrong way may damage the phone.

Step 4: Secure SIM card in Galaxy S9 SIM card tray

You now need to press the SIM card gently so that it is secured in the SIM card tray.

Step 5: Put back the SIM card tray

Once the SIM card is secured, you can push back the SIM card tray into the phone.

Step 6: Power on the phone

If you powered off the phone before the steps, you could now power on the phone.

It may ask you to reboot the phone one more time if some SIM card related phone settings must be changed.

How to use two SIM cards in Galaxy S9 and S9+ (the dual-SIM version only)?

Please refer to this guide (coming soon) on how to use Galaxy S9 SIM card manager and use two SIM cards in dual-SIM version Galaxy S9 and S9+.

How to change mobile network settings in Galaxy S9 and S9+?

For most owners, you do not need to change mobile network settings after you insert the SIM card into Galaxy S9 or S9+.

Most carriers nowadays write all essential settings in the SIM card. After your phone is registered on the network, more settings can be applied to Galaxy S9 or S9+ on the fly.

But occasionally, you may want to change the Galaxy S9 mobile network settings manually.

In Galaxy S9 settings, tap Connections as shown below.

In the connections page, tap Mobile networks as shown above.

You can now access Galaxy S9 mobile network settings:

1. Data roaming.
2. VoLTE calls.
3. Network mode.
4. Access point names (APN).
5. Network operators.

For data roaming, it is always disabled by default whenever you start roaming to avoid expensive roaming data charges.

You need to turn it on manually if you need it. The setting will be reset to disabled when you stop roaming or roam to another carrier.

VoLTE is a new technology allowing you to make calls through 4G LTE network.  The advantages of voLTE include:

• Faster connection.
• Better voice quality. Some carriers may brand voLTE as HD voice for this reason.

In most regions, voLTE is enabled by default if your carrier supports this feature. You can find the voLTE buttons in the Galaxy S9 quick settings panel.

Access point names (APN) settings are always saved in the SIM card. You should never edit them because APN settings may depend on your subscription plans. A few carriers may have some special settings for individual subscribers.

If you mess up the APN settings, you will not be able to receive MMS. You cannot use mobile data as well.

If this happens, you should call your phone company. The support staff should send you an SMS message, and you just need to apply it to reset the APN settings in the SIM card.

By default, the SIM card in Galaxy S9 will try to connect to the fastest available network.

Therefore, it is normally not necessary to manually set up mobile network mode.

But sometimes, you may want to test the network performance of different modes in your area.

As shown above, you can have a few options depending on your mobile plan.  You should always set it to auto connect after such testing.

How to check mobile network connection and signal strength in Galaxy S9 and S9+?

When you find Galaxy S9 or S9+ has problems with the mobile network, you may check the mobile network status to determine whether the problem lies on the SIM card, carrier’s network or the phone.

To check mobile network status in Galaxy S9 and S9+, you need to tap About phone in Galaxy S9 settings as shown below.

Then tap Status as shown above in the about phone page.

In the status page, tap SIM card status as shown below.

In the SIM card status page, you can find the relevant info about the mobile connection.

For example, the signal strength tells you how strong the mobile signal is in the location at that particular time.

If the signal is less than -110 dBm (e.g., -111 dBm), you may have problems to use that mobile network. Calls may be dropped frequenctly if you manage to place the call. Mobile data connection should be very slow.

Mobile network type tells you that your Galaxy S9 is connected to a 2G, 3G (UMTS), HSPA, HSPA+ or LTE network.

Can I use Galaxy S9 or S9+ without a SIM card?

Of course, you can use Galaxy S9 or S9+ without a SIM card.

In this case, you can use Galaxy S9 or S9+ like a WiFi only tablet. You cannot use voice calls. You cannot use mobile data.

But it is not a wise choice. You can get a far better tablet for the same price of S9 or S9+.

Can I convert my single-SIM version Galaxy S9/S9+ to a dual-SIM version one?

No, you cannot convert a single-SIM version Galaxy S9/S9+ to a dual-SIM version one.

There are two problems:

1. The firmware in the single-SIM version Galaxy S9 or S9+ does not support two SIM cards.
2. There is no second SIM card connector in the single SIM version Galaxy S9 or S9+. Changing SIM card tray does not change the hardware inside. Flashing firmware does not solve the issue either.

Anyway, it is a hardware restriction.

So, you should not waste time or money to attempt to convert a single-SIM version Galaxy S9/S9+ to a dual-SIM version one.

Can I use two SIM cards plus a micro SD card in my dual-SIM version of Galaxy S9 and S9+?

You probably watched some video guides on how to use two SIM cards AND a micro SD card in a dual-SIM version Galaxy S9 or S9+.

But I would not recommend you to try it because it may damage the SIM card (and the SD card).  The added thickness may cause some damage to the hardware inside.

If you use an external adapter, you lose waterproofing for Galaxy S9 or S9+. And it is awkward to place the external adapter.   Even worse, it is not very reliable.

How to use two SIM cards on Galaxy S9 and S9+?

Please read this guide on using two SIM cards on Galaxy S9 and S9+.

Do you have any questions on Galaxy S9 SIM card in Galaxy S9 and S9+ now?

If you have any questions or encounter any problems with Galaxy S9 SIM card or mobile network in Galaxy S9 and S9+, please let us know in the comment box below.

The community will help you find the answer.

For the user guide for new features of Samsung Galaxy S9 and S9+, please check Galaxy S9 new features guides page.

For using Galaxy S9 and S9+, please check Galaxy S9 how-to guides page.

For using Galaxy S9 camera, please check Galaxy S9 camera guides page.micro SD

For accessories for Galaxy S9 and S9+, please check Galaxy S9 accessories guides page.

For the official Samsung Galaxy S9 and S9+ user guides (in PDF format), please check Galaxy S9 user guides page.