Why We Never Get The Internet Speeds We Pay For

Internet Speeds

One of the main selling points Internet Service Providers (ISPs) emphasise in promoting their products is the bandwidth that their individual packages allow, in other words, the maximum potential download and upload speeds that each package potentially allows for.

But anyone who has conducted internet connection and speed tests will realise that we never actually achieve these speeds. Why is this?

There are a number of factors that contribute to the reality that we almost never or never actually get advertised speeds on internet packages, mainly concerning the amount and type of traffic and the route and medium over which traffic is sent. But essentially the core of the issue boils down to the difference between bandwidth and throughput.

Let’s look at the issue in more detail.

Internet Speeds – The Sales Pitch Versus the Reality

The issue of promoting internet speeds as part of broadband packages is always a tricky one, as it is understandable that ISPs would want to “dress up” the packages they are offering by advertising theoretical maximum download and upload speeds that they would offer. In fairness the caveat “up to” usually precedes most advertised speeds to indicate this is only a theoretical maximum.

The regulation of how internet packages are advertised differs from country to country. In the UK for instance ISPs have been required for some years now to always include the “up to” phrase when advertising speeds as well as have fine print that explains that speeds are only theoretical and will vary depending on many factors including the time of day.

More recently the regulation stepped up another gear and now requires that UK ISPs at least only advertise “average” peak time internet package speeds and not only theoretical maximums. In this case “average” is defined as a median speed measured at peak time and not only an “up to” figure for the fastest 10% of connections as it was before.

This has made the advertised speeds more fair in the sense that they are a realistic expectation of what a customer can hope to receive and not a theoretical maximum speed they will never actually get. It has impacted upon the advertising as well, with some advertised speeds dropping by as much as 41% following the rule change.

Regulation around this around the rest of the world differs but is usually not as strict as the UK policy now is. But why do advertised and actual speeds differ at all? Should ISPs not be able to deliver their maximum speeds to everyone at all times? Let’s look at why they can’t below.

The Core Issue: The Difference Between Bandwidth and Throughput

Essentially the issue boils down to the difference between bandwidth and throughput, which are two closely related networking terms that capture the difference between theoretical and actual internet speeds that broadband customers get.

Bandwidth is simply defined as the capacity of a medium to carry data. In other words if you have a data carrying medium such as copper cables or fibre strands, then the bandwidth is the maximum possible potential data this medium can handle or carry over a specified time period.

In terms of internet packages this bandwidth itself is restricted by your ISP according to what package you pay for (eg 100 MB/s max speed), so “bandwidth” in this context is still an artificially imposed ceiling, but for the purposes of our explanation it still works as an analogy. The actual bandwidth of the cables that carry your data to and from your house is likely higher.

Throughput is by contrast the measure of the actual transfer of data over a medium over a given time period. In other words, it is what your copper or fibre medium is actually handling or able to transfer at a certain moment time.

To make an analogy, if a highway has 3 lanes and can hold say a certain number of vehicles you could describe this as the bandwidth of the highway, but if some lanes are closed or there are accidents or repairs the actual number of cars at any point in time is less than the maximum potential. You could describe this as the throughput of the highway.

So in ISP internet package terms then the bandwidth would be the maximum advertised “up to” speed that they sell to you as their top speed whereas the throughput would be the actual speeds you get when you conduct a speed test at any moment in time.

Throughput almost never matches bandwidth in any networking environment and you will find this is also true in broadband internet speeds: it is almost impossible to achieve the maximum speed set by your ISP no matter what time of day you test it.

internet speed test

Internet speed tests will almost never match the actual “up to” maximum speeds your ISP package allows for due to a number of reasons

What Causes Actual Internet Speeds to be Lower Than Theoretical Maximums?

So what causes the throughput (actual speed tests in any given moment) to be lower than bandwidth (theoretical maximum speeds available under your package) in broadband internet packages?

Why is the maximum potential speed you could ever achieve under your internet package never or almost never the same the actual speed you get while surfing at any one moment in time?

Throughput differs from bandwidth for many reasons but we will list a couple of the most relevant ones for internet packages below.

1. The Amount of Traffic Passing Through a Network

This is the most obvious factor as everyone will have noticed that internet speeds can particularly suffer at “peak times” in the evenings when most people are at home from work and therefore using the internet for browsing, streaming and so on. More traffic means network congestion which means actual throughput to each individual user will be less.

If there are a lot customers receiving data at the same time on a network, it stands to reason that the infrastructure will be more taxed as it has to try accommodate all these data demands at once. The available bandwidth and resources of the infrastructure has to be shared out amongst more people at busy peak times, so each individual user will get less throughput allocated to them.

By contrast it has been shown that internet speeds tend to be fastest during the early hours when most people are asleep and usage is lower. See here for an article that looks in the subject. The peak hours when internet speeds tend to suffer the most are defined as broadly between 6-12pm but especially between 7-9pm.

2. The Type of Traffic Passing Through a Network

This is really closely related to the first issue, as it depends on the type of browsing internet users are doing that depends how much demands are placed on the infrastructure in terms of bandwidth. More data intensive forms of internet use will place more demands on the network and increase congestion, which means each individual user gets less throughput to play with

So if users on a network are mostly just light browsing and checking emails, then this does not use much bandwidth, but more intensive internet such as video and film streaming and downloading large files does use a lot of bandwidth and so if a lot of people are doing this at once within a particular area or region then internet speeds will tend to slow considerably in that area.

The growth of Netflix streaming is a good example of this, as it is one of the higher data usage things you do online and is increasingly popular as people like to watch a film in the evenings when they get home from work. Lots of people doing this at once obviously demands that a lot of data be sent across the network and therefore average speeds to each user are likely to decrease.

Thankfully the growth in fibre optic internet cabling coverage and high speed internet packages has increased with the demand for high data use streaming services such as Netflix, meaning that even with increased demand for these services and the fall in throughput associated with widespread network use and congestion, most fibre internet packages can still handle these activities even when the speed is significantly reduced in peak hours. 50% of a 100 Mb/s package is still a lot, more than enough for most people!

3. Throttling by Your ISP

Some users can find that their throughput is deliberately lowered by their ISPs even further by what is known as Throttling. This is when your ISP restricts individual internet speeds due to certain restrictions or behaviours. They can for example restrict traffic from torrent or other peer to peer sites deemed to be infringing copyright or other laws.

If your broadband account also has an explicitly stated monthly download cap and you exceed that limit they may also throttle your service and you will have reduced throughput as a result. In fairness this is quite rare now as almost all advertised fibre broadband packages offer “unlimited” data usage subject to a Fair Usage Policy (FUP) that it would be very hard to exceed.

Basically, you’d have to be hammering large file downloads pretty much all day every day for a prolonged period to trigger a FUP, and even then the ISP would often send you a letter warning you before they throttle your speeds.

4. The Structure and Distance of a Network

The difference between potential and actual network speeds also depends on how the network is structured and the distance between the source and destination devices that data is being sent between. The more distance and the more intermediary network devices data has to pass through on its way from A to B, the greater the difference is likely to be between bandwidth potential and actual throughput.

In networking terms this is often referred to as the number of “hops” that data has to pass through before it reaches its destination. In other words, the more devices the data has to hop through on the way, such as servers, boosters, exchanges, switches, and so on, the more likely that throughput or actual internet speeds are likely to be reduced from the potential.

The main reason for this is that a network in general is only as fast as its weakest “hop” or intermediary device. In other words, even if all other devices on a network are perfectly configured and have high bandwidth potential, it only takes one device to have low throughput or not be working properly to create a bottleneck and affect the throughput of the whole network.

The number of hops often increase with distance from point to point on a network, but also depends on the medium the traffic is being sent over. This is where fibre networks have a distinct advantage over copper ones, as fibre cables can carry far more data to begin with but also can carry signals over far greater distance without requiring so many “hops” in the way in the form of signal boosters to maintain the integrity of the traffic.

With some internet packages this can be a huge factor in what speeds customers get, as in some cases their connection is wired as copper not just from their local street cabinet or hub but all the way to their nearest exchange, however far that is.

If this covers some distance, such as a mile or more, then a cooper wired connection will put them at a huge disadvantage over a fibre one as copper has less bandwidth potential to begin with but is also susceptible to signal degradation over that sort of distance.

This is becoming more rare now though thanks to the now widespread availability of Fibre to the Cabinet (FTTC) packages, which are what most advertised fibre internet packages are these days. This means that the connection is wired as fibre down the street cabinet or hub, and then copper the rest of the way to the house, which is usually only several hundred meters or less.

This somewhat reduces the problem of loss of throughput, as almost all of the traffic route to users is now over fibre cable, which has more potential bandwidth capacity and far greater range over long distances with less need for boosting. Hence the growth in availability of high speed internet packages that can deliver 100 MB/s or more download speeds as fibre optic network coverage has increased.

Another step further still in this process is to eliminate the lower bandwidth copper from the network connection altogther and route internet connections as fibre “all the way” to the user.

This is reflected in the growth of the next generation of fibre internet connections, Fibre to the Home/Building/Premises (FTTH/B/P), availability of which is growing across many developed countries. See the next section for more on this.

Main Fibre Optic Providers USA

ProviderPackage 1 Download Speed (mbps)Package 2 Download Speed (mbps)Package 3 Download Speed (mbps)Population Covered (Millions) 2018
Comcast Xfinity100150250100 million*
Verizon Fios10030094034 million*
AT&T Fibre100300100015 million*
Century Link40100100011 million*

See our article for a full breakdown of UK Fibre Optic Internet providers

The Growth of Fibre to the Home (FTTH) Internet For More Stable Speeds

In fairness internet speeds have grown faster and more consistent as the availability of fibre optic internet packages has grown over the conventional cable broadband that preceded it. The former is routed primarily over fibre and the latter primarily over copper, which has the disadvantages with speed and bandwidth that we mentioned above.

However a small but growing number of internet packages are being routed as “full fibre” or Fibre to the Home (FTTH) packages, which means they are fibre connections all the way to a customer’s residence with no copper used at all. This gives them a distinct advantage over even conventional fibre broadband and certainly standard broadband in terms of speed and consistency of the connection.

With fibre strands able carry much more traffic over a much longer range without the need for so many boosters or hops in between, and no copper along the route to limit bandwidth, the growth of FTTH internet has opened up the potential for far faster internet speeds than even the best standard fibre packages.

fibre optic internet cable

A full Fibre to the Home (FTTH) internet package can offer a significant speed and reliability advantage over other internet packages

Availability of FTTH internet varies from country to country, with certain European and Scandinavian countries in particular ahead of the pack on this as they began to target full fibre roll out as early as the mid 2000s.

The United States has a decent and growing level of coverage with over 30 million residential homes having access to FTTH connections, and the UK market is lagging behind with just over a million homes with full FTTH access as of 2018.

If available though, a full FTTH internet connection offers a distinct bandwidth and throughput advantage to users, with speeds of up to 1 Gigabit per second currently available with more capacity potential in the future.

FTTH connections are often also offered as symmetrical, meaning you can get the same download and upload speeds, which is most often not the case with conventional fibre packages which tend to be asymmetrical with a much lower upload speeds than download speeds.

As well as having higher speeds to begin with, full FTTH package speeds also tend to be more reliable and consistent, with speeds not reduced so much at peak times as the full fibre network allows for a more reliable and uninterrupted flow of a larger amount of traffic with no copper along the route slowing traffic down.

Some FTTH providers such as Hyperoptic in the UK even plug this as one of their main selling points, emphasising that their headline speeds are what you will get with no slowdowns or buffering as a full fibre network is less susceptible to interference and being overburdened with traffic demands.

So if you want to get your actual internet speeds (throughput) closer to your maximum potential bandwidth ceiling set by your package, then one option is definitely to look to see if a FTTH connection is available in your area, as a full fibre network will definitely offer a speed and a reliability and consistency advantage, as well as possibly a latency advantage for gamers.

Because of the costs and difficulty of installation though, FTTH packages tend to be most commonly available in new build properties, especially Multiple Occupancy Dwellings (MODs) ie. Large apartment buildings, where there is demand from enough residences to justify installation.

However availability is continuing to grow and as interest in FTTH internet and the symmetrical gigabit speeds it can offer grows, so will the coverage.

FTTH packages also tend to have expensive installation costs running into the hundreds of pounds or dollars, as it often requires digging up parts of driveways and paths to route the connection all the way to a premises. This can make it prohibitively expensive for some, although FTTH providers often have flash offers and deal where they waive some or all of these installation and activation costs.

For our UK readers, see our full article on UK FTTH coverage for more information. It is always worth checking out their sites to see if coverage is available in your area; Hyperoptic are our personal favourite as their coverage is growing rapidly and they are set to hit more than 50 major cities by mid 2019.


Online gamer and general home networking enthusiast. I like to create articles to help people solve common home networking problems.

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