Intercity buses in Germany

Long distance bus services which competed with the railways were prohibited in Germany from 1934 until the market was liberalised on January 1, 2013. The main exceptions were services to and from Berlin and international lines with few stops in Germany, mainly to central and eastern European countries.
Prices are often lower than competing train services, because of fierce competition and because buses don't pay for using roads, whereas trains (even those operated by the state-owned Deutsche Bahn) have to pay for using tracks.
Buses are usually slower than even regional train services, unless the connection by bus is more direct. There are three main reasons for this:

• By German federal law the top speed of buses is at most , whereas "low-speed" trains can go up to and frequently do so with the help of tilting technology and modernized tracks. High speed trains (which almost all long distance trains in Germany are) of course have top speeds of around 250km/h to 300 km/h and are rarely slower than 200km/h for long stretches.
• Buses have to get into and out of cities, often using congested roads, whereas trains simply zip through on dedicated tracks that usually don't slow them down as much.
• By law, bus drivers have to take regular breaks (usually 30 minutes for every four and a half hours traveled). So if a bus is running late (for example because of traffic), the driver might be legally required to take an (unscheduled) break.

As with many forms of infrastructure, the west of Germany is better served than the east, where most companies focus on routes to/from Berlin and major Baltic Sea Coast destinations while mid-sized cities have few or no connections. On the other hand the Berlin - Dresden route is one of the best served in the market with fierce competition driving down prices, mostly due to it being part of the Berlin - Prague route, which is also served by international operators to whom the German domestic market is incidental at best.
Initially the market was extremely lively. Various companies sold tickets on countless routes for less than the price of a cup of coffee to gain market share and brand recognition. Now the market has largely settled down. The number of bus companies (and frequencies/routes) is significantly smaller. The bus companies (which in Germany usually means Flixbus) mainly compete with trains and cars rather than with other bus companies.

On board

Generally speaking the buses are reasonably new and safe, but legroom and seat pitch is often unsatisfactory for large people. Most bus companies sell snacks and drinks on board (or make stops at places where you can buy food), but you should still consider bringing your own as the selection is very limited. Although Wi-Fi is often promised, it is not available in all buses. The internet connection is provided via a normal cellphone signal so bandwidth and access (especially on a full bus) may be limited.

Transporting bicycles

While most companies will transport bicycles for a fee, capacity is usually very limited (hardly more than three or four per bus) and it requires advance notice. Taking a foldable bicycle or putting a bicycle in a bag and declare it normal luggage is less feasible on buses than on trains as there is little space in the bus and the luggage compartments and excess baggage will almost certainly incur a surcharge. It might work out cheaper and more comfortable to take an IC or regional train (ICE trains do not transport bicycles unless in the ways mentioned above, when they are deemed "luggage").

Like long distance trains and most flights in Germany, prices for buses are cheapest when booked well in advance online. It is possible to buy tickets directly from the driver prior to boarding, however expect to pay up to ten times the (advertised) lowest possible rate. Some companies operate their own ticket offices (sometimes integrated into other shops like newspaper shops) at some bus stations. However, ticket offices don't usually sell tickets for competing companies, so you might end up paying a higher price than you would have online. While connecting services with a change of buses are possible, most companies don't guarantee all connections. Delays due to traffic are especially common during holidays and on weekends. If you want to buy your ticket directly from the driver keep in mind that you are not allowed to board a bus if all seats are taken, as standing is illegal on long distance buses in Germany. Most companies also sell tickets through tour operators. However, prices will be if anything higher than the rates online, as there will be some premium for the vendor or the personal service included in the price. Unlike for trains, there are no discounts for frequent travelers. Unlike in aviation, connecting services are never cheaper than any given part of them.
The bus market in Germany has consolidated since it was originally liberalised and Flixbus now controls around 90% of the domestic market. Prices have been slowly increasing. Routes with heavy competition or smaller players on the market still offer some bargains, but clearly the days of ultra-cheap fares are over. Nevertheless, unless the train connection is much inferior in other terms (more changes, longer travel time) a bus ticket bought on the same day will usually be cheaper than a train ticket for the same trip, if the train ticket is not discounted. That said, Deutsche Bahn has introduced a few special offers specifically to compete with bus operators and some aggregator websites even list Deutsche Bahn, so check before you buy a ticket. If you have a BahnCard, note that most aggregators don't figure in BahnCard discounts even if having a BahnCard could entitle you to a discount on the fare. It can be easier to find tickets for slower-but-cheaper trains on bus aggregator websites than it is on DB's own website. Enabling "local transport only" on DB's website excludes IC/EC and ICE displaying only regional trains, which are often slower and cheaper.

Cancellations

In general cancellations are relatively easy but only possible before the scheduled departure of the bus. Flixbus gives you a voucher of the price of your ticket minus €1. Deinbus gives you your money back in the form you paid minus a €3 fee. Onebus lets you chose your money back minus a €5 fee or a full value voucher. Unlike Flixbus you have to cancel 24 hours prior to departure or earlier.

The mainly domestic companies are almost all recent start-ups whereas the international companies have mostly been around for longer.

Mostly domestic

The market for domestic services consolidated a lot in late 2016 with Flixbus taking over almost all domestic competition and some of the others folding. Ever since, prices have been slowly but surely increasing, but are still below those for most comparable train tickets and flights. As no company made any profit in the early stages of the opening of the bus market, it remains to be seen how much prices will rise and whether any new entrants into the market will challenge the dominant position of Flixbus. Buses still do not pay any toll for roads, but some cities are trying to charge for the use of bus station facilities. However, some companies in the past chose to only serve stations with no or low access fees.
Flixbus controls more than 96% of the long distance bus market in Germany. It has the largest network in Germany. Its buses are usually green. The company expanded organically and also bought several competitors, and now has routes in neighboring European countries as well, including connections as far as London. Flixbus owns one single bus mostly due to regulatory issues and subcontracts out virtually all their services. In practice that means the bus you will get may well be a bit older, lack Wifi or electric outlets or have other problems. Flixbus is experimenting with an entertainment portal which can be accessed using on board wifi. However for the time being it will be "on select buses only". " Flixbus Interflix" -a ticket similar to an Interrail pass- is valid for 5 one-way trips over up to three months and costs €99. Flixbus is also known for giving some bus stations somewhat misleading names. For example they call their stop in Kornwestheim "Stuttgart", to suggest it being closer to Stuttgart than it actually is. Flixbus offers reserved seats from 1.50€ with higher prices for what it labels "premium" seats such as the first row in the upper deck of bilevel buses or seats with a table.
Blablabus owned and co-branded by the rideshare company Blablacar launched in 2019 and is the first attempt at breaking the de facto monopoly of Flixbus since its emergence. Similarly to Flixbus, Blablabus does not own buses but subcontracts services. One of their unique selling points is that where their buses don't go, you can book a ride with their ridesharing service and you can combine the two. During its Summer 2019 launch, Blablabus flooded the market with 99 cent tickets, so expect there to be some price competition between the "big two" until the market settles or one of the players withdraws.
Pinkbus also launched in the summer of 2019 with a much more modest selection of destinations, they have two "gimmicks". First is their "no intermediate stops" policy, with all buses running nonstop between Berlin, Düseeldorf and Munich and second is their "flat fares" policy - you'll always pay 25€ for any ticket on any route.
DeinBus has good coverage in the south and southwest of Germany. They also have routes in the north and west of Germany as well as neighboring France, Belgium and the Netherlands. They have a codeshare agreement (similar to airlines) with Dutch operator Citybusexpress, allowing them to offer tickets farther north. DeinBus has a market share of less than 1%.

Mostly international

Eurolines mostly serves eastern Europe but has destinations in other parts of Europe as well. Eurolines predates the opening of the bus market in Germany and has offered some domestic routes under the brand name (Deutsche) Touring for decades.
IC Bus is a subsidiary of Deutsche Bahn and bookable via the regular DB website. They offer very limited international connections to neighboring countries. They are expanding their network. Deutsche Bahn rates and prices (including BahnCard discounts) apply. Booking is through the normal DB website and the booking system treats the buses as if they were intercity trains requiring a reservation.
student agency (sometimes also known as Regiojet) is a Czech company with a network throughout Europe that also serves some domestic routes in Germany. While they don't serve many places in Germany their prices and service (free hot beverages, video screens at every seat) make them worth considering on the routes they do serve. They offer WiFi only in the Czech Republic.
Sindbad is a Polish company serving several destinations in Germany and other countries in Europe. They only serve a handful of stops in Eastern Germany while having a lot more in the West.
Ecolines serves destinations throughout Europe (excluding Scandinavia, Spain, Portugal, Italy, UK, Ireland.)
Leo Express a Czech company with routes from Dresden,Regensburg and Munich to Prague and other destinations in the Czech Republic. Their buses also have "Business Class" seats with more legroom.

Most buses don't operate from dedicated stations. Instead, they typically stop near central (train) stations. Some cities have a central bus station ZOB (Zentraler Omnibus Bahnhof), often centrally located. If you don't know the bus stop, check your ticket: it usually includes an address and a small map of the stop.
Some companies serve more than one station in a city, especially if the city is very big (e.g. Berlin), has more than one major train station (e.g. Dresden) or has a major international airport (e.g. Frankfurt). Be sure to be at the right station and for connecting services check whether the stop where your connection departs from is the same where your bus arrives. If not, figure out how to get from one to the other and how much time that takes. Unless you are going by light rail/subway/tram it would be wise to plan some extra time for traffic congestion.
Many cities discussed constructing bus stations once it became clear that intercity bus travel was here to stay. Cost concerns mean that not all that much has been built as of 2018. Where bus stations do exist, they usually have few shopping options, and they tend to be just as overpriced as convenience stores at gas stations. Some stations have been relocated because of conflict between bus operators and cities, often as a result of congestion. Some stations are closer to the airport than the city center, so check where your bus stops: actually getting downtown may involve a lengthy (and sometimes costly) trip on another mode of transport.

Intercity buses in France - modelled after the German system and some players are or have been active in both markets.