Standard Life has seen a 12% opt-out rate across its auto-enrolment (AE) schemes to date.
The insurer, which offers both a master trust and group personal pension (GPP), has enrolled a number of large employers, including building material supplier Travis Perkins.
Standard Life workplace propositions director Graeme Bold said the company's experience is similar to that seen elsewhere in the industry.
He said: "There's an opt-out rate of around 12% in our schemes at the moment. It does vary by scheme, based on a number of different factors, which is important to consider.
"If you've got an existing scheme with a high level of participation across the scheme, you can see higher opt-out rates. It can also vary between industries and earning levels, which can actually support lower opt-out rates in some cases."
The firm has also noted a trend for lower opt-out rates among new employees in a business that has been enrolled at joining.
Bold said: "It's perhaps because existing employees have already actively chosen not to be in the pension scheme, but it will be interesting to see if the trend continues over time."
Bold added all opt-out requests were received through straight-through-processing channels, with 30% using an online route and 70% choosing an automated telephone service.
The firm has not yet released figures for the total number of people auto-enrolled to date, but is expecting 300,000 new AE members by the end of 2014, and 400,000 by the end of 2018.
Bold said the company is preparing to launch a product for small and medium-sized enterprises (SME) staging in 2014.
He explained: "In July we'll start to roll out a five-stage process for 2014 stagers, which we'll offer online.
"All the experience to date shows forward planning by the employer is fundamental to the success of AE. We're writing to employers and advisers well in advance of staging dates to get them to work with us to continue our successful start."
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