A study of Fortune 100 board pay practices conducted by Compensation Advisory Partners that will be released today has found that at the median, pay for compensation committee chairs rose 25% from 2009 to 2010. At the same time, more boards are doing away with retainers for rank-and-file committee members and increasing the amount of cash or equity amounts in directors’ total compensation packages.

Daniel Laddin, a partner at Compensation Advisory Partners, says chairs of comp committees are spending large chunks of time in between meetings prepping for say-on-pay votes and dealing with regulatory requirements stemming from Dodd-Frank. Most of the work falls squarely on the shoulders of the comp committee chair as the point person for executive compensation.

“There’s a quantum leap in the amount of time required because of the more significant responsibilities of the chair,” says Laddin.

As a result, pay for comp committee chairs among companies in the Fortune 100 rose last year, and the trend is likely to continue among other company boards, says Matt Vnuk, an associate at Compensation Advisory Partners (CAP) who worked on the study.

Companies such as AT&T, Cisco Systems, Hewlett-Packard, IBM and Ingram Micro increased retainers for comp committee chairs last year, according to CAP.

Generally, the pay order among the three main board committees has always been that audit chairs are paid the highest, comp chairs are the second highest, and nominating and governance chairs are third, says Steven Hall, managing director of comp consulting firm Steven Hall & Partners. But recently, Hall says, companies have begun to recognize that the amount of time that compensation committee members spend on their duties is possibly more than what other committees log, and the additional reputational risk and high-priority issues that the comp committee chair is dealing with have grown more significant. Because of the shift, a few companies have even begun to pay comp committee chairs on the same level as audit chairs.

The AT&T board, for example, pays the chairs of its audit and human resources committees the same cash retainer. Both committee chair retainers increased from $20,000 to $25,000 last year. In the same vein, Caterpillar now pays the chairs of the audit and compensation committees the same $20,000 stipend. The audit chair retainer increased from $15,000 to $20,000, however, while the comp committee chair stipend increased from $10,000 to $20,000 last year. DuPont actually reduced the retainer paid to the chair of the audit committee from $25,000 to $20,000 and increased the retainers paid to the chairs of the board’s other committees from $18,000 to $20,000 in 2011. Under the adjusted compensation scheme, all the committee chairs are paid the same retainer.

Hall says comp committees are tasked with meeting additional and updated requirements for CD&A disclosures, working with executives from human resources, legal and accounting departments and working with outside consultants. The work is “not even close to being evenly dispersed” among the other members of the comp committee, says Hall; the bulk of it falls to the chair.

The same is true of other board committees. Boards have continued to eliminate extra retainer fees for committee members other than the chairpersons, says Laddin. About a third of Fortune 100 companies don’t pay directors for service on a committee, a practice that used to be common. Instead, says Vnuk, the board takes the view that all the directors on the board are active in committee work, and the value of committee fees is rolled into the annual cash or equity retainers in pay packages. Doing so also simplifies director fees, he adds.

Historically, Laddin says, there was a predominant pay philosophy that directors should be paid for their time. But among Fortune 100 boards, there’s been a strong migration away from that thinking, he says. Nowadays, directors are paid for their fiduciary oversight, knowledge and overall contribution to the board with a fixed-pay approach, rather than being compensated for individual board, committee and telephone meetings. For many boards, this translates into a total compensation number that is split into equity and cash.

Retainers for committee chairs remain, however, because the workload required differentiates the role. Boards have recognized that the chair roles will be rotated over time and will even out, says Laddin.

And last year, even while comp committee chair pay increased, overall pay for directors remained largely flat, says Vnuk. The large increases in director pay following Sarbanes-Oxley aren’t likely to be repeated anytime soon.

“Over the next few years we continue to expect low- to mid-single-digit increases in director pay as somewhat of a constant,” says Vnuk.

While most companies are keeping audit and governance committee chair retainers flat, pay for chairs of compensation committees is rising as a result of the heavy workloads associated with say on pay and additional scrutiny of executive compensation plans.