Where are you from? The Netherlands has tax treaties with different countries that may offer you some additional options.
The Netherlands calculates a maximum tax free contribution to your pension each year based on your income. If you contributed less than you were allowed to (pensioengat), you can invest the difference between your actual and allowed contributions in special retirement investments that usually offer tax advantages. A gap like this can be due to getting a bonus or a raise.
After looking around, the investments available are either a special savings account (banksparen) or an annuity (lijfrente). Your allowed contributions to both will be tax deductible and the investment itself is excluded from wealth tax (box 3 taxes). I also see Aegon offering an "investment annuity" that lets you invest in any of 7 of their mutual funds until a certain date at which time you liquidate and use the proceeds to fund an annuity.
With the Dutch retirement options, wou will not in general get the same freedom of choice or low costs associated with IRAs in the US. I'm not sure about ISAs in the UK. It's also important to check any tax agreements between countries to ensure your chosen investment vehicle gets the tax advantaged treatment in your home country as it does in the Netherlands. For US citizens, this is important even when living abroad. For others, it is important if you return to your home country and still have this investment.
If you are a US citizen, you have an additional option. The US / Dutch tax treaty allows you to make these contributions to preexisting (i.e. you had these before moving to NL) retirement accounts in the US like an IRA. Note that in practice it may be difficult to contribute to an existing Roth IRA because you would need to have earned income after the foreign income tax deduction but less than the maximum income for a Roth contribution.
