The Financial Ombudsman Service (FOS) expects to receive 16,000 new pension and investment related cases in 2017/18 - a 22% increase on its December forecast of 13,100.
Despite this FOS said it had budgeted for total operating costs to go down by £30m on its original forecast for the coming year, at £263.5m versus £295.2m. This still represents a £14.8m increase on last year's operating costs, however.
The Ombudsman's total operating income is also expected to fall to £241.9m compared to the £276.6m it forecasted back in December. This represents a £13.8m increase on the total operating income of 2016/17.
Levies will still account for £27m of its budget - the same as originally forecasted last December. Individual case fees will remain at £550 for the fifth year in a row.
More SIPP claims?
The FOS has not pointed to any particular reason for the forecasted rise in pension and investment complaints, but its most recent complaint statistics, published in February, showed a substantial rise in self-invested personal pensions (SIPP) complaints between October and December last year.
It received 18% more complaints about the products in that period than in the previous quarter and 38% more than the average 274 complaints per quarter it received in 2015/16.
The Financial Services Compensation Scheme has already budgeted to levy life and pension advisers a record £171m in 2017/18.
Last November, the lifeboat fund also confirmed its intention to raise an interim levy for 2016/17 of £36m for life and pensions advisers to fund "unexpected" numbers of SIPP-related claims.
Chief executive Mark Neale said the claims largely "related to advice to switch pension funds into high-risk investments".
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