The Pension Protection Fund (PPF) has announced the 2016/17 levy estimate will be set at £615m, a £20m drop on the 2015/16 figure.
The PPF said it had reduced the figure because of a lower risk of employer insolvencies.
While the PPF expected to see a further increase in underfunding risk as a result of recent market conditions, such as low gilt yields, this was offset by improvements in insolvency risk scores.
David Taylor, general counsel at the PPF, said: "Our estimate for how much we will collect in 2016/17 - £615 million, is lower than last year's estimate of £635 million. This reduction reflects improvements in the Experian scores that scheme employers and guarantors are receiving, balanced by a deterioration in scheme funding."
According to a consultation paper on its levy rules, the PPF said for the sake of stability the rules for 2016/17 would be "substantially the same as for 2015/16".
Kevin Burgess, head of Punter Southall's levy consulting team, said: "Schemes should check their invoice when it arrives to ensure it is correct and any invoices that are not as expected should be queried.
"While the deadlines to provide new information to influence the 2015/16 levies have passed, there may still be scope to appeal invoices that are not calculated in accordance with the PPF's published rules."
The PPF previously said it would move to a new insolvency risk provider Experian with a new levy model for assessing insolvency risk.
Burgess said: "With the move to Experian, it is important to check that Experian is using the correct data. This is taken from the sponsor's financial accounts and it is important to check that Experian has correctly interpreted the accounts."
The PPF also said a move to Financial Reporting Standard 102 (FRS102) would be likely to affect some firms' risk scores from the year 2017/18, but the full-year effect would only be seen in 2018/19.
Nick Griggs, head of corporate consulting at Barnett Waddingham, said: "The PPF has indicated that a key consideration will be the impact of a move to the new accounting standard FRS 102. This change could result in a higher levy for multi-employer schemes. Employers may want to investigate the potential impact of this issue as early as possible."
The PPF is also launching a series of seminars for trustees and advisers in a number of cities about type A contingent assets. These assets help reduce insolvency risk or reduce the size of a claim in the event of insolvency, and they include parent company or group guarantees.
The consultation on levy rules runs until 22 October.