Why estimate the gap before choosing?
Italy's public pension system is pay-as-you-go: today's workers' contributions pay the pensions of those who have already retired. It works, but it returns a benefit tied to your actual contribution history — not to your last salary. On average the public pension covers 70-75% of last income, but for broken careers, income that grew over time, or moves between employment and self-employment, the gap can be wider.
Supplementary pension schemes exist precisely to build, with your own saving capacity, the part the public system does not cover. Before choosing where to contribute it is worth knowing how much is actually missing, not just generically "how much is worth saving".
What supplementary pension schemes exist?
The first fork in the road is between three routes. Negotiated funds arise from sector-level collective bargaining: contained costs and, often, an employer contribution that is triggered by joining. Open funds are offered by banks and insurers, open to anyone regardless of sector. Individual pension plans are insurance contracts, aimed at those looking for more customisation in how the policy is built.
There is no single best scheme: the choice depends on your employment contract, on any employer contribution already available, and on how much you value flexibility against cost.
How do you choose the right investment line?
Within each scheme you also choose an investment line — from the most cautious, geared towards government bonds and fixed income, to the most dynamic, with a larger equity component. The basic rule is simple: the more years remain before retirement, the more it makes sense to tolerate short-term swings in search of higher long-term returns. Those approaching retirement gradually shift capital towards more cautious lines, so as not to suffer a market downturn just as the benefit is about to be paid.