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 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.

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.

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.

If your phone or SIM card is lost or stolen and automatic recharge is on, this could be a serious problem.

To prevent this, log in to your account and activate the option to block your service immediately after you notice your phone or SIM card is missing. You can find this option in the My SIM Cards menu. Your OneSimCard service for this SIM card number will be instantly blocked. The remaining balance on your lost SIM can be transferred to another SIM card on your account or you can order a replacement SIM card if you would like to keep your phone numbers from the lost SIM. However, the existing data package can’t be transferred to the new SIM card.

Alternatively, you can contact customer service online or call 001-617-313-8888 for assistance.

Note: You can always dial 00 instead of + when making outgoing calls. For example, to reach OneSimCard customer service in the USA you can just dial 001 617 3138888.

You should consult the phone manual for this info. Different manufacturers have specific ways to access the '+' key, so make sure you know yours.

Here are few known ways:

• Bosch: Press and hold the star (*) key until the "+" sign appears.
• Motorola: Press and hold the zero key until the "+" sign appears.
• Nokia: Press the star (*) key twice in rapid succession.
• Pocket PC: Pull up the keyboard, hit the <123> button in the top left corner, and select "+" from the resulting screen.
• Samsung: Press and hold the zero key until the "+" sign appears.
• Sony Ericsson: Press and hold the zero key until the "+" sign appears.
• Treo 270: Press the blue button and then the "G" key.

For Universal, Expedition, and eSIM World SIM cards, many U.S. and Canadian carriers can charge more than $3/minute to connect to an Estonian mobile number, the primary mobile number for a OneSimCard global SIM card. Your SIM card includes a U.S. number which will be much less expensive for people to call.

Callers can also use one of the Common Access Numbers (CAN) that we provide to you free of charge in more than 10 countries. Your OneSimCard account will simply be charged an additional 20c/min to the incoming rate in the country you are in to receive those calls. There is also the option of ordering a dedicated Personal Extra Number (PEN) in Canada and many other countries that will forward all calls directly to your OneSimCard cell phone. You can see the list of countries where PENs are available here:

You can order a Personal Extra Number when placing your order or later at any time by logging in to your account. Visit our Rates & Coverage page and choose any country to view all rates.

If you would prefer for the caller to pay for calls made, we recommend they buy Peanuts Prepaid. Using this service would guarantee a connection to your OneSimCard mobile phone from the U.S and Canada for 20c/min and it is very easy to use without switching your LD carrier.

For DataMax and DataMax eSIM, if you chose to use SIM VOIP app, your friends and family will call the PEN number you are assigned, so in most cases, there will be no tariff for them to call you, and the cost to receive the call is only $0.01/Minute.

OneSimCard will work with almost any unlocked GSM tri-band or quad-band cell phone. A partial list of compatible cell phones that we have tested can be viewed here.

If you need to unlock the phone, we suggest contacting your carrier or phone manufacturer for unlocking information or services.

If your phone is not a quad-band phone, please make sure that the bands of your phone are those required in the country of your travel. You can look it up here.

If you are still unsure whether your cell phone is compatible, contact support or purchase an international cell phone and SIM card bundle from us, which all come preloaded with our international SIM card, $10 balance  and OneSimCard Apps Installed.

Yes. Your Universal, Expedition and eSIM World OneSimCard mobile number can currently be forwarded to EU, Canada, USA, Russia, Ukraine and Belarus numbers. It's 100% free to forward your OneSimCard phone number to many countries including to U.S. or Canadian numbers. Forwarding to some countries, as well as to satellite phones, will carry a forwarding charge as listed in the Rates & Coverage page on OneSimCard.com.

To enable/disable call forwarding from your online account:

Log in at OneSimCard.com and go to the My SIM Cards menu. Select your SIM card number and enable/disable Call Forwarding on this screen.

To enable/disable call forwarding from your phone:

Dial *146*081*XXXXXXXXXXXXX# and press Send/Talk (where XXXXXXXXXXXXX is the forward-to number in international format: 00+countrycode+number)

Newer SIM cards use *81* instead of *081*

Example: to forward to U.S. number 1-617-555-1212, dial *146*081*0016175551212# and press Send/Talk.

If you get an "Unknown Format?" message, dial *146*81*0016175551212#

To disable call forwarding, dial *146*080# and press Send/Talk. If you get an "Unknown Format?" message dial *146*80# and press Send/Talk.