Once you have an unlocked GSM phone with a SIM card from either Kolbi, Claro, or Mobistar, you are ready to start using your phone. Costa Rica phone numbers are 8-digit phone numbers. A call to any number in Costa Rica is considered a local call. Some useful local phone numbers are:
911 – all emergencies
117 – police
118 – fire
113 – domestic directory assistance
114 – international directory assistance (costs about 20 colones)

Since the balance on your SIM card is colones, all amounts are given in colones. The conversion rate floats around 500 colones to $1 US. Thus, a 5 colones coin is 1 penny US, a 25 colones coin is a nickel, a 50 colones coin is a dime, and a 100 colones coin is a quarter.

With Kolbi, you are not charged for incoming calls. You are charged 28 colones to 34 colones per minute for outgoing local calls. The charge for outgoing local SMS text message is 1.70 colones per message. For an international SMS message, the rate is 34 colones per text message. Kolbi uses MIDA for making international calls. MIDA divides the world into six zones. The following table gives the current cost per zone in colones:

Zone	Cost per Minute (colones)	Countries
A	130	United States, Canada, Mexico, Puerto Rico, Hawaii, Alaska, U.S. Virgin Islands
B	220	South America, Caribbean except Cuba, South Korea, Taiwan and Japan
C1	160	Guatemala, Honduras, El Salvador, Belize and Panama
C2	160	Nicaragua
D	270	Europe, Singapore, Thailand, Australia and New Zealand
E	510	Cuba and Rest of World

Like Kolbi, Claro only charges for outgoing calls and messages. An outgoing local call costs 34 colones per minute. An outgoing SMS, or MMS, local text message cost 1.7 colones per message. International text messaages cost 65 colones per message. Claro divides their International call rates into a lot more categories. There is a distinction between calling a Claro number or a non-Claro number. For calls to the US, expect to pay the exception rate, which is currently 199 colones per minute.

The local call rates and SMS rates for Movistar are the same as Kolbi. International SMS messages are 85 colones per message. International calls are charged according to the following table:

Cost per Minute (colones)	Countries
130	United States, Canada, Mexico, Puerto Rico
220	South America, Caribbean except Cuba
160	Central America
270	Europe
270	Australia and New Zealand
210	Taiwan, Japan, Singapore, Thailand
565	Cuba and Rest of World

When you initially purchase a SIM card, it is good for 120 days. If you do not recharge your card within the 120 days, it goes into an inactive state for 30 days. After the 30 day grace period, your SIM card is no longer valid. During the grace period, you just need to recharge your card for any amount. If you recharge your card for even 100 colones during the 120 day period, it remains active. If you don’t recharge your card within the 30 day grace period, it is no longer a valid card, and you lose any charge on the card. The simple rule is that if you recharge your card at least once in any 120 day period, it remains active.

Promotions are the name of the game. Kolbi sends out a text message that says today is a double day. Even though the message is in Spanish, it doesn’t take long before you know what it means. Any recharge that you apply to the SIM card during the day is doubled. This is Kolbi’s response to the promotions offered by Claro and Movistar. The promotions usually do not apply to International phone calls, but do apply to International text messages.