Updated from Dec. 13 to include additional information regarding T-Mobile data plan.
NEW YORK (TheStreet) -- Finding the best monthly wireless service plan used to be easier. You went into a store, selected a phone, chose how many voice minutes you needed and got a contract price. You signed a piece of paper and were on your way.
Now getting a mobile phone is more complicated. You need to decide on a payment plan (all the carriers say theirs are better than their competitors') and how much wireless data you need each month (unlimited voice calls and messaging are generally standard now). And you need to figure out whether your family or group qualifies for a discount. You also need to know which carrier provides the best service in the places you need it. Low monthly charges won't matter without a signal.
Let's compare the four major U.S. cellular providers and find the best plans for your brand new Apple (AAPL) iPhone 6 or 6 Plus.
AT&T (T) calls its handset purchase offering AT&T Next. Once you decide which iPhone model you want (the 6, 6 Plus, 5S or 5C) you only have to pay the sales tax upfront. AT&T will then split the actual cost of the phone into 20, 24 or 30 monthly payments. With the Next plan you can trade in that iPhone for a newer model after either 12, 18 or 24 payments.
In the unlikely event you grow tired of your new iPhone, you can opt to trade it for a different phone after as few as two months. Under AT&T's Pay to Upgrade option, you make a lump payment of the remaining 12, 18 or 24 monthly phone payments you originally agreed to.
OK, that's just dealing with the actual phone. Then you add the monthly service charges.
Those are a little more straightforward, but just a little bit. One GB of wireless data under AT&T's Mobile Sharing Plan costs $25. That's in addition to the discounted monthly Next access charge of $25, for a total of $50. If you go to 2 GB of data, that adds up to $65 a month. And 5 GB has a $95 monthly service charge.
Remember, that's in addition to the monthly payout for the phone.
All of this does get cheaper if you buy as a family or group. The more monthly wireless data you share, the cheaper it comes out to per person. AT&T's largest bundle offers 100 GB of shared data for $375 a month, plus the devices' access charges.
Sprint (S) also splits its iPhone leasing options from its monthly service options. For iPhones, Sprint offers a special Simply Unlimited plan. You qualify if you buy your new iPhone with Sprint's Easy Pay monthly installments or a leasing plan called "iPhone for Life."
Sprint charges $50 per month for "unlimited talk, text and data."
Sounds great. But there's a lot of fine print to deal with.
First of all there's a $36 per-line activation fee. The plan says it "Includes unlimited domestic Long Distance calling, texting and data. Third-party content/downloads are add'l charge. Int'l svcs are not included."
And then there what that unlimited plan doesn't include: "Monthly charges exclude taxes & Sprint Surcharges [incl. USF charge of up to 16.10% (varies quarterly), up to $2.50 Admin. & .40 Reg. /line/mo. & fees by area (approx. 5-20%)]."
All carriers add fees and collect taxes, but you need to make sure you read everything you can find to know exactly what your bill will be for the next two years.
Sprint also offers Family Sharing plans, with a $15 monthly access charge. Data "buckets" run from $20 a month for only 1 GB to $100 for 20 GB, and up to $225 a month for 150 GB. As many as 10 users can take advantage of these bulk rates.
T-Mobile (TMUS) was the first major carrier to emphasize both the phone leasing trend (T-Mobile calls it "Jump!") and monthly service charges, which the self-proclaimed "un-carrier" calls "Simple Choice."
There's a $50 per month 1 GB LTE data plan. Actually, you get 2.5 GB per line through 2015. Add $30 for another phone and $10 for each additional phone on the same bill. If you have four or more phones, each user gets 4.5 GB per month through 2015.
And now there's a new unlimited plan for two or more family members. For $100 a month, two people get unlimited 4G/LTE data, along with all the other unlimited services. The only real limit is that the deal is a "limited time offer." For two users, the choice is either for each to pay $80 a month for 1 GB of data, or $100 a month for unlimited data for both.
T-Mobile has also announced it will offer the rolling over of any unused data to customers with plans of 3 GB or more each month. Beginning in January instead of losing those unused megabytes DataStash will let customers bank them in their accounts for a year. Then, it can be used when it's really needed. T-Mobile is giving subscribers an extra 10 GB of data at the start to sweeten the deal.
Verizon (VZ) Edge is the handset purchase and payout plan for the nation's (self-dubbed) "largest, most reliable nationwide carrier." Edge customers can opt for a single-line monthly service plan for $45 with 1 GB of data, or $65 a month for 2 GB. If you're not enrolled in Verizon Edge, add $15 a month to those prices.
The company's bulk-rate discount offerings are called the More Everything Plan. You buy the phone (via Edge, or pay the full price up front) and then a $40 monthly access fee, plus the cost of your bucket of shared data.
That's where you have many options. For example, Verizon offers 3 GB for $60, 10 GB for $80, 20 GB for $150, all the way up to 150 GB for $750 a month. Verizon offers a monthly access fee discount to Edge users.
As with all the different plan offerings from all four carriers, you need to read and make sure you understand all the fees, taxes and conditions buried in the fine print before you agree to spend hundreds or even thousands of dollars each month on cell phone services.
-- Written by Gary Krakow in New York.
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