Of course you can! Simply send and receive SMS texts according to your phone's user manual or from the OneSimCard Menu. Receiving SMS is always free. Sending an SMS (text message) is $0.15 - $1.50 depending on the country.

SMS messages sent to a OneSimCard phone should always be sent to the main OneSimCard mobile number rather than to an optional Extra Number, with the exception of new SMS enabled numbers in USA, Canada and UK Mobile available since Jun 3rd, 2014. When replying from OneSimCard phone to the SMS received on USA or Canada SMS capable PEN using Europe & More sim or the Expedition SIM, the main number of the SIM that starts with 372 will be displayed on the text receiver phone. With the Universal SIM, you can select what caller ID will be shown on the SMS receiving party phone.

You can also send SMS messages from OneSim VOIP app at much lower rates. Note: for Physical 3-in-1 Datamax and Damax eSIM all SMS messages MUST be sent through the OneSim VoIP App with PEN.

You can also send a free SMS message to any OneSimCard customer from our web site or by sending email to [email protected], where 372XXXXXXXX is the OneSimCard primary mobile phone number. The maximum number of daily SMS sent to the SIM over email or web is 25.

Please bear in mind that message should be sent in English characters. In addition, it should not be longer than 160 characters including spaces.

These 2 options of sending SMS by email provide completely free way of communicating, as it is usually free for you to send the email and costs nothing for the OneSimCard customer to receive a text message.

To make a call:

• Dial 00-CountryCode-AreaCode-Number and press the TALK/SEND button.
  Example: To call OneSimCard Support in the USA you would dial 00 1 617 3138888 and press TALK/SEND. 

With Europe & More, Univesal and eSIM World that do not use the callback to make a call, you will just get connected.
 
With OneSimCard Plus SIM or Expedition (formerly Data & Roam) SIMs:

After pressing the TALK/SEND button you will see a variable message on the screen (for example 'Wait for call') which you can ignore and your phone will ring back in a few seconds. Answer this ring as you normally would answer any incoming call. Your call will then be connected.

If you are unsure about how to properly dial an international number, follow this link for detailed country by country dialing instructions.

For Physical 3-in-1 DataMax, and DataMax eSIM cards, you can place calls using our low cost OneSIM VoIP service. OneSim VoIP costs much less than traditional voice roaming.

For Universal, Expedition, & eSIM World ONLY: Just dial 099 "Send" from your OneSimCard phone and in few minutes the balance will be displayed on the screen of your phone. Customers with iPhones can use OneSimCard Assist app to check balances and many other things.

You can always check your current balance by logging onto your OneSimCard account at www.onesimcard.com.

In order to add airtime instantly, simply register a credit card with us on our website.

There are several ways to add airtime to your OneSimCard service.
Automatic Recharge - recommended:

1. Just log on to your account at www.onesimcard.com and set auto-recharge in the Recharge Menu. Funds will be added to your account when your balance drops below the threshold you set.

From the phone using your credit card (Universal, Expedition and eSIM World only):

1. a) From the phone dial pad dial 098YYYY*XX. Talk. YYYY = Last 4 digits of the credit card used last at OneSimCard.com. YY = Amount from 25 to 99 USD

 For example, if you need to add $50 and the last 4 digits of the credit card registered with us is  8654:
You would dial 0988654*50 and press TALK. In few seconds you will get a confirmation message with  your new balance.
* is a star character located on the keypad
From the phone using 1SIM Fund:
 a) From the phone dialpad dial 098YYYY*XX. Talk. YYYY -  4 digits PIN you created in 1SIM FUND menu. YY Amount from 25 to 99 USD

 For example, if you need to add $50 and the 1SIM FUND PIN is  8654:
You would dial 0988654*50 and press TALK. In few seconds you will get a confirmation message with  your new balance.
* is a star character located on the keypad

From the OneSimCard.com web interface:

1. You must log in at www.onesimcard.com each time you wish to add funds.
2. The minimum recharge amount is US $25.00
3. Using Recharge PIN purchased from a dealer:

If you purchased a recharge PIN from OneSimCard Authorized dealer, you can recharge your account from OneSimCard handset from OneSimCard - Add Credit menu. When the Add Credit menu is selected, enter the 10-digit PIN and press the Talk (Send) button. 

There are no monthly fees or connection charges for using OneSimCard international cell phone service.

If you order an optional Personal Extra Number (PEN), there is a small periodic fee to keep the PEN active based on how you choose to be billed (from $1.67 per month). There is also an additional charge to receive a call through any Extra Number. View our Rates & Coverage page and click on any country to view our available Extra Numbers and associated costs.

Through a unique partnership with Viber, your primary OneSimCard number (+372) can be called free of charge for any Viber user! (requires activation and special dialing instructions, see below)

HOW: When this feature is activated, Viber users can call OneSimCard numbers for free by using a special dialing format +372800XXXXXXXX, where XXXXXXXX is the rest of the OneSimCard phone number after 372. For example, a OneSimCard user with the phone number +37212345678 should be called by dialing +37280012345678.

TO ACTIVATE: Log in to your OneSimCard account and go to the My SIM Cards menu. Scroll down to where it says "Incoming Viber Calls" and click Enable to activate this option.

COST: The call is free for the Viber user. The cost of receiving the Viber call is the same as receiving a call through a Personal Extra Number (PEN), i.e. the regular incoming call rate in the country you are in plus 20c/min. In countries with free incoming calls, like Italy or Japan, the cost will be just 20c/min.

PLEASE NOTE:

• When dialing in Viber, if Viber user chooses the Estonian country code in the menu then they should just dial 800XXXXXXXX because the +372 is added automatically.
• If the “free calls to OneSimCard from Viber” option is not activated for a particular OneSimCard number, when a Viber user dials +372800XXXXXXXX they will hear an automatic message: “The mobile phone is either switched off or out of coverage area.”

PLEASE NOTE: Viber is not available for the DataMax or DataMax eSIM

The SIM card does not offer SMS service to short code numbers

For Universal E, Expedition E, eSIM World E, eSIM Asiania, Plus, Europe & More, & Standard SIM Cards, the international SIM card phone number and account will expire if no outgoing usage is made for 12 months. The outgoing usage could be any of the following: Call made from the phone, SMS sent from the phone or any Data Usage.

Personal Extra Numbers will stay active as long as they have been funded properly.

The SIM card balance is valid for 10 months. The balance will continuously roll over to the next 10 month period provided that at least $25 is added within 10 months after the last recharge.

If the balance expires, the service can still be used after a new recharge of the SIM card.

For Physical 3-in-1 DataMax & DataMax eSIM SIM Cards, the SIM card and account will expire if no outgoing usage is made for 12 months. The outgoing usage could be any of the following: Call made from the OneSIM VoIP App, SMS sent from the OneSim VoIP app or any Data Usage.

Personal Extra Numbers will stay active as long as they have been funded properly and the SIM hasn’t expired. If the SIM card expires, but then is restored ($10 Restoration Fee applies), the PEN will be re-attached to the SIM card, as long as the PEN hasn’t expired based on the time period for which the PEN was purchased.

The SIM card balance is valid for 10 months. The balance will continuously roll over to the next 10-month period provided that at least $25 is added within 10 months after the last recharge.

If the SIM card balance expires, the SIM will expire and be removed from the account after 7 days, unless there is a data package currently active on the SIM (not a future activation). If there is no balance on the SIM and the active data package expires, the SIM will expire 7 days following the expiration of the active data package. So, to keep the SIM active you need to either keep a balance on the SIM or an active data package.

An expired SIM can be restored for a $10.00 restoration fee plus a recharge of at least $25.00.