As our phones get faster and have better screens and more processing power, it's natural that they gobble up more cellular data. An unlimited data plan can be a great fit for our data-hungry devices. However, keeping track of the ever-changing unlimited plans, prices and features can be frustrating. But that's why we're here. 
 
 Last year, the "unlimited data" wars heated up between the four major carriers in the US. Each one tried to outdo the others in terms of price and how much data you actually got. Unlimited data is kind of like a bottomless cup of coffee at a diner: At some point you'll be cut off. 
 
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 For most people, these large data plans should be more than enough. But to help make sense of what you actually get, we compared the unlimited plans from AT&T, Sprint, T-Mobile and Verizon and all the fine print that came with them. 
 
 Editors' note: This article was originally published on Feb. 13, 2017. Since that time, AT&T, Sprint, T-Mobile and Verizon all announced multiple changes to their unlimited data plans. The information below reflects the prices and features of unlimited plans as of April 27, 2018. 
 
 Data limits and throttling 
 
 The unlimited plans from the big four carriers all come with unlimited talk, texting and data. But there's a catch -- when you hit a certain data limit, your data speeds are slowed down or your data needs are sent to the back of the line. These are the data limits for each carrier: 
 
 Cost for a single line 
 
 Obviously, one of the reasons unlimited plans exist is to offer lots of data at a reasonable price -- reasonable enough to beat overage charges. Here's what a single line of unlimited data on each carrier costs: 
 
 Peter Cade/Getty Images 
 
 A few notes on these plans: 
 
 For both of the AT&T unlimited plans, there might be an additional $30 monthly device access fee for your smartphone. So that $45 a month could go up to $75 and $60 up to $90. 
 
 The plans for AT&T, Sprint and Verizon do not include taxes, surcharges or additional fees. 
 
 All of the plans include an autopay discount: $5 a month for Sprint, T-Mobile or Verizon and $10 a month for AT&T. 
 
 T-Mobile One and Verizon "Go Unlimited" plans limit people to standard-definition video and only 3G hotspot support. 
 
 AT&T's Unlimited Choice plan limits people to standard-definition video with streaming speeds capped at 1.5 Mbps and doesn't include hotspot data. 
 
 Comparison of single line unlimited data plans with autopay discounts applied Carrier Data throttled after Video streaming Unlimited data monthly cost Single-line data plan cost for 2 years Verizon "Beyond Unlimited" 22GB/month HD $85 $2,040 T-Mobile One Plus 50GB/month HD $80 $1,920 Verizon "Go Unlimited" 22GB/month SD $75 $1,800 T-Mobile One 50GB/month SD $70 $1,680 AT&T Unlimited Plus Enhanced* 22GB/month HD $60 ($90*) $1,440 ($2,160*) Sprint Unlimited Freedom 23GB/month HD $60 $1,440 AT&T Unlimited Choice Enhanced 22GB/month SD $45 ($75*) $1,080 ($1,800*) 
 
 *AT&T may apply a $30 monthly device access fee for your smartphone 
 
 Cost for additional lines 
 
 If you need additional lines of unlimited data, each of the big four has a range of prices: 
 
 AT&T Unlimited Choice Enhanced: $45 per month for the first line, $80 for two and $160 for four. Like its single line plans, AT&T might apply a $30 smartphone device access fee for each phone on the plan. 
 
 AT&T Unlimited Plus Enhanced: $48 per month for the first line, $110 for two and $180 for four. And don't forget, that $30 smartphone device access fee. On a four line plan that could increase the price from $180 to $320 -- almost twice the cost. 
 
 Sprint Unlimited Freedom: $60 per month for the first line, $90 for two lines and $130 for four lines. The four line price is good until June 30, 2019 after which the price increases to $160. 
 
 T-Mobile One: $70 per month for one line, $120 for two and $160 for four. 
 
 T-Mobile One Plus: $80 per month for the first line, $140 for two and $200 for four. 
 
 Verizon "Go Unlimited": $75 per month for the first line, $130 for two and $160 for four. 
 
 Verizon "Beyond Unlimited": $85 per month for the first line, $160 for two and $200 for four. 
 
 All multi-line unlimited plans have an autopay discount applied: $5 a month for Sprint, T-Mobile or Verizon and $20 a month for AT&T. 
 
 AT&T's prices also reflect an included multi-line discount: $10 for three lines or $20 for four lines or more. 
 
 Comparison of multiple line monthly costs with autopay discount applied Carrier First line Cost Second line cost Third line cost Fourth line cost Total monthly cost for four lines Verizon "Beyond Unlimited" $85 $75 $20 $20 $200 AT&T Unlimited Plus Enhanced $45 ($75*) $35 ($65*) $40 ($70*) $40 ($70*) $160 ($320*) T-Mobile One Plus $80 $35 $46 $24 $180 T-Mobile One $70 $30 $41 $19 $160 Verizon "Go Unlimited" $75 $55 $20 $10 $160 AT&T Unlimited Choice Enhanced $60 ($90*) $50 ($80*) $40 ($70*) $40 ($70*) $190 ($350*) Sprint Unlimited Freedom $60 $40 $30 $0 ($30**) $160 ($190**) 
 
 *AT&T may apply a $30 monthly device access fee for each phone on your plan. 
 
 **Sprint prices include a $30 discount on the fourth line that's good through June 30, 2019. 
 
 Unlimited prepaid 
 
 Both Verizon and T-Mobile offer prepaid plans with unlimited data. Verizon's "Prepaid Unlimited" plan is $75 per month. The "Prepaid Unlimited" plan lacks tethering and mobile hotspot support, and only offers standard-definition video streaming. 
 
 The T-Mobile prepaid plan, aptly named One Prepaid, costs $75 a month: $5 a month more than its postpaid One plan. T-Mobile One Prepaid doesn't include support for LTE hotspot data and limits video streaming to standard definition. You do get support for hotspot data at 3G speeds and you can buy a high-definition video day pass at $3 a pop. 
 
 HD video vs. SD video 
 
 Sprint includes 1080p high-definition video streaming in its plan. However, Verizon only includes 720p HD video in its "Beyond Unlimited" plan. T-Mobile One and AT&T Unlimited Choice Enhanced limit video streaming to 480p standard definition (think DVD quality). 
 
 Josh Miller/CNET 
 
 Verizon's "Go Unlimited" and "Prepaid Unlimited" plans and T-Mobile's One Prepaid unlimited plan also limit video streaming to 480p standard definition. 
 
 For more money, you can upgrade plans to include 1080p high-definition video streaming. 
 
 Mobile hotspot data 
 
 If you use your phone as a mobile hotspot. All carriers offer hotspots with LTE data speeds, but not all plans do. Also, keep in mind there are limits on how much data you can use. Some plans like Verizon's "Go Unlimited" give you unlimited mobile hotspot streaming at 3G speeds. 
 
 Verizon "Beyond Unlimited" -- 15GB per month of mobile hotspot LTE data 
 
 Verizon "Go Unlimited" -- hotspot access at 3G data speeds 
 
 T-Mobile One -- hotspot access only at 3G data speeds 
 
 T-Mobile One Plus -- 10GB per month of mobile hotspot LTE data 
 
 Sprint Unlimited Freedom -- 10GB per month of mobile hotspot LTE data 
 
 AT&T Unlimited Plus Enhanced -- 15GB per month of mobile hotspot LTE data 
 
 AT&T Unlimited Choice Enhanced -- no mobile hotspot data 
 
 The final word 
 
 It is truly wonderful to have unlimited data options from all four major US carriers. This comparison of costs and features is just part of the bigger picture though. Keep in mind other factors that will hit your wallet: cost of phone, extended warranties, taxes, surcharges and activation fees -- the last three T-Mobile has folded into its pricing. It's also worth considering network coverage and the quality of that coverage, too. 
 
 Links to each carriers' unlimited plans: Sprint, AT&T, T-Mobile, Verizon.
– AT&T says any cellphone customer can sign up for unlimited data plans starting Friday, a change that comes just days after Verizon announced a similar move and Sprint and T-Mobile beefed up their offerings. All four major cellphone providers now offer unlimited plans, a major reversal from a few years ago, per AP. AT&T's version costs the same as Verizon's for a family of four at $180, but it's pricier for an individual—$100 per month vs. $80, while Sprint is at $50 (that goes up $10 in a year) and T-Mobile at $70. Those figures are from CNET, which has a detailed breakdown of all the plans. By CNET's calculations, the two-year cost for a single line of unlimited data is as follows: AT&T, $2,400; Verizon, $1,920; T-Mobile, $1,680; and Sprint, $1,320. All the plans will slow down data speeds once you hit a certain limit, with AT&T and Verizon setting that at 22GB, Sprint at 23GB, and T-Mobile at 28GB. Sprint also said Thursday that it's letting unlimited customers watch video in high definition rather than DVD quality. T-Mobile announced a similar change Monday after Verizon said HD video was included. AT&T's unlimited plan degrades video to DVD quality, but customers can turn HD video back on for free.