The AT&T plan charges less per gigabyte as you buy more data. (Courtesy of AT&T/Courtey of AT&T)

Following in the footsteps of Verizon Wireless, AT&T announced Wednesday that it has new plans that allow customers to share data.

The new plans will be available in late August and start at a cheaper rate than Verizon's — $40 for 1GB of data, plus $45 for each smartphone versus $50 and $40 on Verizon — but end up being more or less similar in the end.

One key difference is that AT&T’s smartphone fee gets smaller as you add more data, whereas Verizon’s fee is always $40. Both companies’ 4GB plans, for example, are $70 for the data, plus $40 for each smartphone. At the top end, AT&T will offer 20 GB of data for $200 and $30 for each smartphone, compared to Verizon’s 10 GB plan that offers the data for $100.

Also, Verizon offers more plans for smaller data usage, going from 1GB to 2GB, then up by two-gigabyte increments until it hits a 10GB plan. AT&T offers 1GB, 4GB, 6GB, 10 GB, 15 GB and 20 GB plans.

Both companies also offer unlimited text messaging and voice minutes with the shared plans.

So what should you buy? If you’re a family that uses a lot of data, AT&T is probably the most cost-effective, whereas those who want to use less data might want to stick with Verizon’s gradual steps.

That said, switching to a shared plan isn’t a good deal for everyone. It would be ideal for those paying for several data plans now, but find that, say, one family member never gets near their data limit while another is constantly pulling in overage fees. But if you’re on your own, AT&T has a plan that’s $30 for 3GB per month, which is a much better value than paying $40 for 1GB.

You should definitely figure out what is the best value for your money before considering a different AT&T plan, both in terms of how much you pay per GB and how much you pay overall.

AT&T customers will have a choice as to whether they want to stick with the provider’s existing plans or opt for one of the shared plans, in contrast to Verizon’s approach to replace most of its traditional plans with the new model.

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