WhatsApp calls are 90% cheaper than those using airtime — here’s how SA mobile networks compare

• If you’re still using airtime to make cell-to-cell calls, now’s definitely the time to stop.
• Calls using data via services like WhatsApp are about 90% cheaper than if you use traditional airtime.
• In rand value, a five minute WhatsApp call can save you as much as R4.60 – depending on your service provider and data bundle.
• Although several variables exist, even a WhatsApp video call is likely cheaper per minute than a traditional airtime-funded cell phone call.
• Here’s how much it costs to make a WhatsApp call on cellphone providers in South Africa.
• For more stories go to www.BusinessInsider.co.za.

There’s almost no justifiable reason to make a cellphone to cellphone call using anything but data and WhatsApp, or a similar voice-over-IP (VoIP) application.

Although exactly how much data you use on a WhatsApp call varies and is not something the company officially reports, even in a worst-case scenario you won’t come close to paying more than you will if you use traditional airtime.

According to various online sources and our own cursory call studies, a typical WhatsApp call without video uses 0.5MB and 0.75MB per minute. The amount of data you use may vary depending on call quality and signal strength (whether you’re using 2G, 3G, or 4G) and if one or both parties are connected using different data speeds. There’s also a low data setting on WhatsApp that may reduce both call quality and data usage, though they don’t specify by how much.

For this study, Business Insider assumed a likely worst-case scenario where a WhatsApp voice call uses an average of 0.75MB per minute. Using this as a yard stick, a WhatsApp call shouldn’t cost more than 6c per minute, depending on the service provider and data bundle size.

Comparatively, a one-minute call using pre-paid airtime costs between 66c and 79c per minute.

This means you’ll save between 62 and 75 cents per minute – or as much as 96.45% – if you use WhatsApp over airtime. Although in rand value this isn’t dramatic, talk for longer and it can have a reasonable impact. On a 15-minute call, for example, you’ll save close to R10 by choosing a VoIP alternative.

You can also realise some saving with WhatsApp video calls. Studies suggest that a WhatsApp voice call uses about 5MB per minute. On a typical 1GB package, this means a WhatsApp video call costs roughly 40c a minute, which is still lower than any pre-paid airtime cost per minute.

Quite how much you save in percentage terms varies according to the cost of airtime and data at mobile service providers. But customers at MTN, which currently has the highest per-minute airtime rate, stand to gain the most by switching to WhatsApp calls – with a price difference of up to 96.45% depending on the specific data bundle.

Here’s how the cost of a WhatsApp call compares to those using airtime, assuming you use an average of 0.75MB per minute:

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