How to use recharge cards on Nigerian mobile networks

Nigerian networks have various denominations of recharge cards. 

MTN Nigeria

MTN Nigeria recharge cards are yellow in colour. To recharge an MTN SIM card, a subscriber incorporates the recharge PIN in the following USSD format: *555*PIN# Send/Ok. MTN Nigeria' recharge card PIN has 12 digits. If the PIN is 2345 5478 1110, input *555*234554781110# and press Send or Ok. Dial *556# to verify account balance.

Etisalat Nigeria

Etisalat Nigeria recharge cards are black in colour and contain a 15-digit PIN. To recharge an Etisalat SIM card, a subscriber incorporates the recharge PIN in the following USSD format:
*222*PIN# Send/Ok. If the PIN is 580 389 318 308 778, input *222*580389318308778# and press Send or Ok. Dial *232# to check account balance.

You can also recharge your friend or family member's Etisalat line with a recharge card, directly from your Etisalat line. To recharge another person's line straight from your phone, dial *222*PIN*Recipient'sNumber#. If the PIN is 580 389 318 308 778, and the beneficiary's number is 08090001111, dial*222*580389318308778*08090001111#. Subscriber  08090001111 will be credited and be notified of the transaction.

Airtel Nigeria

Airtel Nigeria recharge cards are red in colour and contain a 16-digit PIN. To recharge an Airtel SIM card, a subscriber incorporates the recharge PIN in the following USSD format: *126*PIN# Send/Ok. If the PIN is 2345 5478 1110 9999, input *126*2345547811109999# and press Send or Ok. Dial *123# to check account balance.

Glo Nigeria

Glo Nigeria recharge cards are green in colour and contain a 15-digit PIN. To recharge a Glo SIM card, a subscriber incorporates the recharge PIN in the following USSD format: *123*PIN# Send/Ok. If the PIN is 2345 5478 1110 777, input *555*234554781110777# and press Send or Ok.
Dial #124# to check account balance.

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