I'm a recent graduate in CS currently living in Germany and looking for jobs as a junior Java developer. So I'm trying to understand more about contracts and things like that.
I have the following questions regarding overtime:
Am I required to work overtime?
Is overtime always paid?
If overtime is not always paid, why is that legal? It's unfair to the employee, so I'm wondering why governments/unions allow such things. Especially in Germany!
Working time in Germany is regulated by the "Arbeitszeitgesetz (ArbZG)", the law concerning time spent working.
§3 says a working day is 8 hours maximum. You may do overtime up to two hours per day if your avarage working time in 6 months does not exceed 8 hours per day. There may be exceptions from this rule for people working shifts and people who are on call.
In practice that means most companies are organized so that people have a kind of account that saves "time". You do overtime this week, you may leave earlier another week to balance it. If leaving early is not possible on your job, maybe you have to save enough overtime to drop a whole shift. Different companies have different regulations though and most of them are fine. They will be stated clearly in the contract.
§9 say you must not work sundays. It also lists two pages of exceptions, like restaurants, emergency services, taxi drivers and the like.
So nobody can make you work more than 10 hours a day or on sundays in a normal software developers job. That's illegal. Doing IT support may have different rules though, after all they are on call and their work on sunday might as well be an emergency for the company.
That said, in practice in software development, nobody even knows these laws and nobody is unionized. Not because people don't know better, but because laws and unions are to protect those people that cannot help themselves. And software developers in Germany can. If I don't like my company? I quit and work for another. Companies are having trouble finding the right people, so treating your developers badly will result in them leaving.
I've been in the industry for 15 years and I have not once had a manager order overtime. Only stupid ones would even try. However, I have not met a single developer who would not have volunteered to do overtime, sometimes even over the legal limit and on sundays, just because they knew the company needed it. Not volunteering to do overtime on weekdays would probably be looked down upon by your coworkers, while coming in on weekends would be very, very rare. Working times for developers are mostly flexible in Germany and that includes that you might do 50 hours in one week and 35 in the next two. Software development is rarely a 9-to-5 job. It's more like a somewhere-between-7-and-10-to-when-it's-done job.
There are exceptions to any rule. If you are looking for a 9-to-5 job with no overtime you may want to look into heavily unionized companies or even civil services or administration. Most do work on strict regulations and most get paid like... well... lets just say most developers stay away from jobs that offer a payment calculated using the public service payscale ("Tarifvertrag Öffentlicher Dienst"). They are somewhat secure and boring and pay that way.
Sometimes you may see a clause in a contract that says "Überstunden sind mit dem Gehalt abgegolten", meaning your overtime is already paid for by your normal salary. Basically it means you won't get paid for overtime because you salary is already above average. It's your choice if you think the other parts of the contract are worth it. Remember, nobody in his right mind will order overtime in software development. You volunteer.
So
While the other answers already gave a good overview regarding the overtime culture in the software industry of Germany itself, I would like to add some facts, because I think the legal situation isn't really completely described here.
You are only supposed to do what's inside your contract. There is no legal possible way for your employer to force you to do a lot of overtime if it's not mentioned in your contract.
If we talk about contracts containing a clause that states that any overtime is included in your basic salary, some employers try to put clauses like that into their contracts, but this is basically illegal.
There is only one exception to this. A clause like that is allowed if the job is considered high paid (the exact border of what is considered high paid is derived from the Beitragsbemessungsgrenze which for 2015 means a basic salary of more then 6050€/month in the west (or 5200€/month in the eastern states).
As already stated there is a lack of IT experts in Germany in the moment, which puts employees in a more favorable position compared to other industries or countries. If you are searching for entry positions and have poor language skills on the other hand I feel like you'll have to make some trade-offs regarding overtime and salary for your first job.
Regarding the Arbeitszeitgesetz mentioned in some other answers: I think most small software companies (10-50 employees) don't really care about the very strict rules in this law (or it's on paper only). That's especially true for startup-kind-companies.
When you´re required to work overtime:
a) Your contract (or collective agreement of your branche) includes it, together with more details
b) Emergency situations, whatever this means, but only if a max. weekly work time isn´t exceeded
Either it is paid with money, or you´ll get additional vacation time which can be used later.
It´s possible to agree on a fixed amount of overtime compensation each month (ie. your base salary is more than usual, but there is "unpaid" overtime).
No compensation at all is not possible.
It depends on the law and the fine print of your contract, and also on the membership of your employer in the employers' side of collective bargaining agreements.
The law quoted by nvoigt sets the absolute maximum on your working hours. Note that legally Saturday is a working day, so you can have a 48-hour-average working week. (In most industries, unions have negotiated a much lower average.)
If your employer joined an employers' organization, union agreements may apply to you even if you're no union member yourself. As nvoigt points out, that's unusual in the IT sector, but not unheard of. Especially if you work in the IT department of a non-IT company.
If your company has a works council, they might have a say in overtime regulations. Many IT companies' employees don't bother to elect one, believing that they can care for themselves.
deviantfan is not quite right insofar as you can agree to sign a work contract where overtime is not paid, provided the total work time complies with the law. People who do so presumably negotiated a higher base salary than people who negotiated that overtime is paid.
