I have been offered salary exchange
Salary exchange means that you reduce your salary in exchange for another benefit, for example extra occupational pension.
If you earn less than the limit for the national pension (i.e. 8,07 income base amounts, or SEK 49,967 per month), it may not be profitable for you. Discuss with your employer what is best for you.
ITP 1 and ITP 2 handle salary exchange in different ways.
Within ITP 2, the employer can continue to report your original salary before the exchange, so that your retirement pension and family pension are not affected. Your disability pension will be based on your salary after the exchange though.
Within ITP 1, your employer can only report your salary after exchange. You therefore have to make an agreement with your employer to pay the same premium as before the exchange. This is then done as an addition, a so-called complementary premium. The salary exchanged to an extra occupational pension payment can be payed to the existing ITPK insurance or the ITP 1 insurance.