Elfenstar: as an employee you have a couple of attractive options even if you decide to leave Germany eventually.
1. bAV (betriebliche Altersvorsorge): within this you deduct up to 210.- EUR per month from your gross salary and put that into an investment plan based on funds/shares or the likes giving you really profits over time. Since the money comes out of your gross salary, only a share of it is from your net and the rest is saved taxes, public pension and unemployment fees etc. If you go to another company within Germany, this plan is portable. If you leave Germany you can either cash in or let the money rest in the account until pension time and then decide whether you want a pension or lump-sum payment. Since your employer also benefits from this (because reduction of your gross salary equals a reduction of his on-top costs from your salary) you might even convince the employer to rise your salary at the same time some... After some of these plans who deducted to high costs in the first couple of years in the past (like
life insurance and off-shore plans usually do) have been disputed successfully at courts, nowadays plans are available where right from the start your invested money works for you, thus it even makes sense for only a couple of years. The total performance/yield on your invested net pay from add-on gross pay plus profits from the invested funds makes this quite attractive, actually
2.
RIESTER plan: don't be dismayed by the current rule that you have to pay back the direct subsidies and tax break money you receive when saving with a RIESTER plan if you ever decide to leave Germany eventually.
First: this rule is under disput at the European court by complaint through the European Commission against Germany and I am pretty sure that this rule will be cashiered before long at least for EU citizen
Secondly: while according to the current rule you have to pay back said subsidies, you are allowed to keep the profits generate with them. Since they subsidies normally amount to 30-40 % of the money you paid in cash, this pushes up any yield your own money generates by 1-2 % points over time since it acts like an interest free loan to you
Thirdly: now the nicest thing is, that if you leave Germany in a couple of year you can claim a deferal of the back-payment until pension time, i.e. you can let the subsidies work for you a couple of years/decades more all the while you do not need to pay interest on it. So in the end the result from compound interest is really neat if then you wold really have to pay back the money at all, which I doubt (see explanation above for dispute at European court).
But here to you need to choose a plan which does not deduct too much costs/fees/commission at the very beginning, but a small number of such plans are available with a good selection of investment funds.
The only governement subsidized plan not working for Expats planning to leave Germany eventually and wanting to get the cash instead of a pension are RÜRUP plans because they do not allow anything but receiving a pension starting at the earliest from age 60 til the rest of your life, even though they are quite attractive too from a tax-saving point of view.
What you definetly should avoid are any life insurance pension plans like most Germans have due to the low yield and high costs.
Happy to provide more information if required,
Cheerio