The pension company decides what bid/offer spread to charge. It is a charge. The most common bid/offer spread for individual policies is 5%. It's important to note that only some policies have any bid/offer spread. Off the top of my head, all new policies being set up now don't have a bid/offer spread, so it only applies to older policies already set up. In the case of Zurich Life, being the example you used, they have some policies with bid/offer spreads and some without so you'd need to know whether the specific policy has one or not and then look at the relevant set of fund prices.