The amount has been increased from £5,000 because the FSA said the cost of winding down an operator was unlikely to cost less than £20,000.
The move has provoked criticism from some providers such as AJ Bell. They are concerned that commercial property, an increasingly popular investment for Sipp plans, may be treated as as "non-standard" asset. This could mean potentially higher capital adequacy requirements for operators that allow commercial property to be included in a Sipp and mean higher costs.
Total capital requirements will take into account the amount of assets under administration and the additional capital surcharge for operators holding non-standard assets as these take longer to wind down.
David Geale, head of investment policy at the FSA, said: "Put simply: the more assets you have under administration- the more capital you will need and if some of those assets happen to be more risky you will need even more."
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However, the FSA said it would operate an "economy of scale" in that Sipp operators can transfer some scheme with the same assets in bulk.
Finally, the FSA proposes the core capital must be held in a form that is realisable within a year while capital held against a surcharge must be realisable within 30 days.
Mr Geale said: "While the Sipp market has grown substantially over time, the capital regime has not changed and needs bringing up to date. These proposals reflect the volume, range and complexity of assets now being put into Sipps and ultimately will protect investors better in the unfortunate event an operator is wound down.
"We believe these proposals are pragmatic and proportionate but this is a consultation so we want to hear from the industry and consumer groups to ensure they are also balanced."
The consultation will close on 22 February 2013 and there will be a transitional period of one year between the publication of the final rules and implementation by firms.

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