OverviewComcast, based in Philadelphia, Pennsylvania, is the largest residential internet service provider (ISP) in the United States. It focuses on cable internet technology to deliver speeds of up to 2,000 Mbps to homes, which is significantly faster than other options on the market.Yet the company's reputation is one of the worst in the country. The main complaints surrounding Comcast concern the customer service and the pricing, which is often much higher than typical internet costs in areas with limited competition.ProsFast internet speedsBroad availabilityAccess to Wi-Fi hotspotsConsPoor customer serviceHigh pricesData capsServiceComcast Xfinity holds an enviable position as one of the fastest internet service providers out there, which is important when you want to cut the cord and watch a lot of streaming services. The lowest available speed is 15 Mbps, while the highest is a whopping 2,000 Mbps. You do have to contend with a data cap of 1 TB in most plans, with the exceptions being the top-tier plan and prepaid internet plans.When you subscribe to Comcast Xfinity internet, you gain access to millions of Wi-Fi hotspots available around the United States. Access to these can come in handy if you're traveling around the country or need to quickly connect to the Internet while you're running errands.Comcast customers can get the Xfinity xFi Gateway, a device that functions as an all-in-one modem and router. You get notifications when new people and devices connect to your network, so you always know exactly what's going on. Useful features give you a lot of control over your network: you can even schedule different internet availability times for different family members.Comcast's network uses cable internet, so your available bandwidth is dependent on the number of people using cable around you. During high demand times, your speeds can take a nosedive. You might not notice it when you're streaming on a 2 Gbps plan, but it's definitely going to hurt on a 15 Mbps plan.Comcast is often the fastest option in many markets, but available speeds can vary significantly from place to place. The prices also lack uniformity and appear tied to the competition (or lack thereof) in the area.Norton's Security Online and VPN service help you stay protected against cyber attackers that could attempt to steal your personal information or compromise your devices.Customer ServiceComcast was named the worst company in America in 2010 and 2014, and angry customers have long reported abysmal service and support. Comcast is even less popular than the IRS (literally). A few of the most common issues that customers brought up include different customer service representatives offering different and conflicting information; charges for “unreturned” equipment that had, in fact, been returned; extremely long hold times for customer service; canceled or severely delayed technician visits; and broken promises about 2-hour appointment windows. Comcast's confusing price increases and accidental overcharges can be tough to unravel as you jump from one unhelpful representative to the next.Surveys by various customer satisfaction research groups have found minimal improvement by Comcast over the years. Comcast has excellent speeds, but if you have problems with your service, you're probably going to experience a lot of frustration.You can try to fix the problems yourself by using the tools available on the Xfinity website. You can check to see if there is a service outage, track estimated technician arrival time and run through troubleshooting guides to start working on your issue.AvailabilityComcast is available in 40 states and services more than 40 percent of cable internet subscribers in the United States. They sit in the number one spot for cable internet access and frequently are the only option in a market, or at least the only one offering speeds sufficient for streaming video. Over 26.5 million people use the company's services.PriceComcast Xfinity pricing is not uniform at all, so you could be paying drastically different fees for your internet service than customers are in other locations. In general, Comcast is the most expensive provider in the market. Sometimes that makes sense, since Comcast is offering higher speeds than the competition. In other cases, Comcast appears to charge more because there are no other Internet service providers available in a given region. The pricing scale is broad: prices generally starts at around $24.99 per month and can go up to nearly $300 per month.Comcast offers both contract and non-contract plans. Since Comcast frequently hikes up the price when you leave the promotional period, you'll want to read carefully to find out what your bill will be after the first year.Installation fees, equipment costs, activation fees and other surcharges are also likely to pop up without being properly disclosed. Billing errors are commonplace, according to customer reviews, so keep a close eye on the numbers when you sign up.Comcast also offers bundles with television and home phone services, which can reduce the price of internet service significantly.ContractsYou get to choose whether or not you want to have a two-year contract with your Comcast Xfinity internet plan. The no-contract options are significantly more expensive for much lower service levels than the two-year internet contracts.Cancellation policyComcast offers a money-back guarantee for customers who cancel within 30 days. If you cancel outside of this period, however, you're subject to an early termination fee that varies based on your service tier and the time left on your contract. You also get charged if you fail to return equipment to Comcast.SummaryComcast has exceptional speeds in many markets, which helps customers overlook the many failings of the company on the customer service front. The prices are higher than average for many areas, and you can expect especially high prices if there are not many other ISPs available in your area.