Depending on how you use Skype, you may be able to chat away all day and never spend a penny. 

Skype-to-Skype calls, whether via video or voice only, are free whether the participants are in the same country or in different continents all together. 

If you want to use Skype to call someone who uses a cellphone or landline, however, you can use Skype credit at varying rates to do so.

Here's how, first using Skype on your computer.

1. Log into Skype on your Mac or PC and click on your profile picture.

2. Click on the words "Add Skype Credit."

3. Click the "Continue" button within the "Skype Credit" box that suits your preference (dollar amount, e.g.)

Click "Add Skype Steven John/Business Insider

4. Choose your payment method (or add a new one) and click "Pay now."

Skype also offers an auto-recharge option where Skype Credit will be automatically charged to your account if it ever falls below $2, so you don't risk a dropped chat. Steven John/Business Insider

1. Open the Skype app on your iPhone or Android and then tap your profile picture at the top of your screen.

Note that your current balance is displayed on this tab. Steven John/Business Insider

3. Tap the amount of credit you wish to add, then tap the "Add $ credit" button and confirm the payment.

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