LONDON (Reuters) - Job changes are a common feature of 21st century employment, meaning many people have built up a string of pension pots. Here are the key facts about consolidating pension funds within a self-invested personal pension (SIPP):

* Switching a defined contribution (money purchase) pension into a SIPP is relatively straightforward, but you should only go down this route if you think you have sufficient understanding of investment markets to manage your fund choices.

* Watch, too, for tax-free cash entitlements. Some occupational schemes allow savers to take out more than the standard 25 percent that a SIPP allows.

* Old-style retirement annuity contracts often offer guaranteed annuity rates that you would not be able to get on the open market. By moving to a SIPP you would lose access to this valuable benefit.

* Some company schemes might have negotiated lower charges than you can get through a SIPP, and may have access to external funds that are better than the "default" option.

* Exit penalties on some with-profit pension funds might make it not worthwhile switching out. But new money might be better placed in another pension product than a poorly performing with-profits contract.

* Switching benefits out of a defined benefit (final salary) scheme is almost never advisable. Professional advice is a must.

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