Cell C recently extended its free WhatsApp promotion to 30 June 2015, which lets its contract and MegaBonus prepaid subscribers use WhatsApp without incurring data costs.

Under the terms of the promotion, qualifying WhatsApp users can send text, pictures, voice, and video messages over the mobile messaging service without incurring charges.

The questions is, with WhatsApp rolling out its voice calling feature in recent weeks – letting Android users “invite” one another to use the voice over Internet Protocol service – will the free data extend to WhatsApp voice?

Cell C initially played it safe when asked if the promotion would cover voice calling, with head of marketing Doug Mattheus saying he couldn’t answer the question directly.

He said Cell C chose to embrace disruptive over-the-top players like WhatsApp, and hopefully it would work well for the mobile operator.

Mattheus added that since they have chosen not to oppose the march of messaging services such as WhatsApp, it is very difficult to U-turn now.

When asked again whether Cell C would zero-rate WhatsApp voice calling traffic, a spokesperson for the company just said: “WhatsApp voice calling is still in beta testing.”

Testing WhatsApp voice calling on Cell C

The only way to find out if you’ll be paying for WhatsApp voice calling on Cell C is to run a test.

We placed a WhatsApp call to a contract Cell C SIM and let the Cell C user do the bulk of the talking.

After a minute the call was terminated and the data available in the subscriber’s bundle was compared to the amount they started out with before the call.

In total, 490 kilobytes of data was deducted.

It would seem that – at least for the moment – WhatsApp voice calling is not included in Cell C’s free data promotion.

Thanks to Kevin for his assistance in testing WhatsApp voice calling on Cell C.

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