Exhibit 24

GREAT-WEST LIFE & ANNUITY INSURANCE COMPANY

POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that I, Brian Walsh, member of the Board of Directors of Great-West Life & Annuity Insurance Company, a Colorado corporation, do hereby constitute and appoint R.G. Schultz and B.A. Byrne, and each of them, as my true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for me and in my name, place and stead, in any and all capacities to execute registration statements of the SecureFoundation® Group Fixed Deferred Annuity Smart Future Certificate of Great-West Life & Annuity Insurance Company on Form S-1, or any successor form of registration statement of the Securities and Exchange Commission, filed under the Securities Act of 1933, and any and all amendments thereto, with all exhibits, instruments, and other documents necessary or appropriate in connection therewith, and to file with the Securities and Exchange Commission or any other regulatory authority as may be necessary or desirable, hereby ratifying and confirming all and every act and thing requisite to all intents and purposes that said attorney in fact and agent or his substitute, may lawfully do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, I have hereunto set my hand this 25^th day of February, 2014.

GREAT-WEST LIFE & ANNUITY INSURANCE COMPANY

POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that I, Greg Tretiak, member of the Board of Directors of Great-West Life & Annuity Insurance Company, a Colorado corporation, do hereby constitute and appoint R.G. Schultz and B.A. Byrne, and each of them, as my true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for me and in my name, place and stead, in any and all capacities to execute registration statements of the SecureFoundation® Group Fixed Deferred Annuity Smart Future Certificate of Great-West Life & Annuity Insurance Company on Form S-1, or any successor form of registration statement of the Securities and Exchange Commission, filed under the Securities Act of 1933, and any and all amendments thereto, with all exhibits, instruments, and other documents necessary or appropriate in connection therewith, and to file with the Securities and Exchange Commission or any other regulatory authority as may be necessary or desirable, hereby ratifying and confirming all and every act and thing requisite to all intents and purposes that said attorney in fact and agent or his substitute, may lawfully do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, I have hereunto set my hand this 26^th day of February, 2014.

GREAT-WEST LIFE & ANNUITY INSURANCE COMPANY

POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that I, Raymond Royer, member of the Board of Directors of Great-West Life & Annuity Insurance Company, a Colorado corporation, do hereby constitute and appoint R.G. Schultz and B.A. Byrne, and each of them, as my true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for me and in my name, place and stead, in any and all capacities to execute registration statements of the SecureFoundation® Group Fixed Deferred Annuity Smart Future Certificate of Great-West Life & Annuity Insurance Company on Form S-1, or any successor form of registration statement of the Securities and Exchange Commission, filed under the Securities Act of 1933, and any and all amendments thereto, with all exhibits, instruments, and other documents necessary or appropriate in connection therewith, and to file with the Securities and Exchange Commission or any other regulatory authority as may be necessary or desirable, hereby ratifying and confirming all and every act and thing requisite to all intents and purposes that said attorney in fact and agent or his substitute, may lawfully do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, I have hereunto set my hand this 25^th day of February, 2014.

GREAT-WEST LIFE & ANNUITY INSURANCE COMPANY

POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that I, Henri-Paul Rousseau, member of the Board of Directors of Great-West Life & Annuity Insurance Company, a Colorado corporation, do hereby constitute and appoint R.G. Schultz and B.A. Byrne, and each of them, as my true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for me and in my name, place and stead, in any and all capacities to execute registration statements of the SecureFoundation® Group Fixed Deferred Annuity Smart Future Certificate of Great-West Life & Annuity Insurance Company on Form S-1, or any successor form of registration statement of the Securities and Exchange Commission, filed under the Securities Act of 1933, and any and all amendments thereto, with all exhibits, instruments, and other documents necessary or appropriate in connection therewith, and to file with the Securities and Exchange Commission or any other regulatory authority as may be necessary or desirable, hereby ratifying and confirming all and every act and thing requisite to all intents and purposes that said attorney in fact and agent or his substitute, may lawfully do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, I have hereunto set my hand this 21^st day of February, 2014.

GREAT-WEST LIFE & ANNUITY INSURANCE COMPANY

POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that I, Michel Plessis-Bélair, member of the Board of Directors of Great-West Life & Annuity Insurance Company, a Colorado corporation, do hereby constitute and appoint R.G. Schultz and B.A. Byrne, and each of them, as my true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for me and in my name, place and stead, in any and all capacities to execute registration statements of the SecureFoundation® Group Fixed Deferred Annuity Smart Future ertificate of Great-West Life & Annuity Insurance Company on Form S-1, or any successor form of registration statement of the Securities and Exchange Commission, filed under the Securities Act of 1933, and any and all amendments thereto, with all exhibits, instruments, and other documents necessary or appropriate in connection therewith, and to file with the Securities and Exchange Commission or any other regulatory authority as may be necessary or desirable, hereby ratifying and confirming all and every act and thing requisite to all intents and purposes that said attorney in fact and agent or his substitute, may lawfully do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, I have hereunto set my hand this 25^th day of February, 2014.

GREAT-WEST LIFE & ANNUITY INSURANCE COMPANY

POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that I, Jeffrey Orr, Chair of the Board of Great-West Life & Annuity Insurance Company, a Colorado corporation, do hereby constitute and appoint R.G. Schultz and B.A. Byrne, and each of them, as my true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for me and in my name, place and stead, in any and all capacities to execute registration statements of the SecureFoundation® Group Fixed Deferred Annuity Smart Future Certificate of Great-West Life & Annuity Insurance Company on Form S-1, or any successor form of registration statement of the Securities and Exchange Commission, filed under the Securities Act of 1933, and any and all amendments thereto, with all exhibits, instruments, and other documents necessary or appropriate in connection therewith, and to file with the Securities and Exchange Commission or any other regulatory authority as may be necessary or desirable, hereby ratifying and confirming all and every act and thing requisite to all intents and purposes that said attorney in fact and agent or his substitute, may lawfully do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, I have hereunto set my hand this 28^th day of February, 2014.

GREAT-WEST LIFE & ANNUITY INSURANCE COMPANY

POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that I, Paul Mahon, member of the Board of Directors of Great-West Life & Annuity Insurance Company, a Colorado corporation, do hereby constitute and appoint R.G. Schultz and B.A. Byrne, and each of them, as my true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for me and in my name, place and stead, in any and all capacities to execute registration statements of the SecureFoundation® Group Fixed Deferred Annuity Smart Future Certificate of Great-West Life & Annuity Insurance Company on Form S-1, or any successor form of registration statement of the Securities and Exchange Commission, filed under the Securities Act of 1933, and any and all amendments thereto, with all exhibits, instruments, and other documents necessary or appropriate in connection therewith, and to file with the Securities and Exchange Commission or any other regulatory authority as may be necessary or desirable, hereby ratifying and confirming all and every act and thing requisite to all intents and purposes that said attorney in fact and agent or his substitute, may lawfully do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, I have hereunto set my hand this 21^st day of February, 2014.

GREAT-WEST LIFE & ANNUITY INSURANCE COMPANY

POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that I, Alain Louvel, member of the Board of Directors of Great-West Life & Annuity Insurance Company, a Colorado corporation, do hereby constitute and appoint R.G. Schultz and B.A. Byrne, and each of them, as my true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for me and in my name, place and stead, in any and all capacities to execute registration statements of the SecureFoundation® Group Fixed Deferred Annuity Smart Future Certificate of Great-West Life & Annuity Insurance Company on Form S-1, or any successor form of registration statement of the Securities and Exchange Commission, filed under the Securities Act of 1933, and any and all amendments thereto, with all exhibits, instruments, and other documents necessary or appropriate in connection therewith, and to file with the Securities and Exchange Commission or any other regulatory authority as may be necessary or desirable, hereby ratifying and confirming all and every act and thing requisite to all intents and purposes that said attorney in fact and agent or his substitute, may lawfully do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, I have hereunto set my hand this 25^th day of February, 2014.

GREAT-WEST LIFE & ANNUITY INSURANCE COMPANY

POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that I, Paul Desmarais, Jr., member of the Board of Directors of Great-West Life & Annuity Insurance Company, a Colorado corporation, do hereby constitute and appoint R.G. Schultz and B.A. Byrne, and each of them, as my true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for me and in my name, place and stead, in any and all capacities to execute registration statements of the SecureFoundation® Group Fixed Deferred Annuity Smart Future Certificate of Great-West Life & Annuity Insurance Company on Form S-1, or any successor form of registration statement of the Securities and Exchange Commission, filed under the Securities Act of 1933, and any and all amendments thereto, with all exhibits, instruments, and other documents necessary or appropriate in connection therewith, and to file with the Securities and Exchange Commission or any other regulatory authority as may be necessary or desirable, hereby ratifying and confirming all and every act and thing requisite to all intents and purposes that said attorney in fact and agent or his substitute, may lawfully do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, I have hereunto set my hand this 21^st day of February, 2014.

GREAT-WEST LIFE & ANNUITY INSURANCE COMPANY

POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that I, André Desmarais, member of the Board of Directors of Great-West Life & Annuity Insurance Company, a Colorado corporation, do hereby constitute and appoint R.G. Schultz and B.A. Byrne, and each of them, as my true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for me and in my name, place and stead, in any and all capacities to execute registration statements of the SecureFoundation® Group Fixed Deferred Annuity Smart Future Certificate of Great-West Life & Annuity Insurance Company on Form S-1, or any successor form of registration statement of the Securities and Exchange Commission, filed under the Securities Act of 1933, and any and all amendments thereto, with all exhibits, instruments, and other documents necessary or appropriate in connection therewith, and to file with the Securities and Exchange Commission or any other regulatory authority as may be necessary or desirable, hereby ratifying and confirming all and every act and thing requisite to all intents and purposes that said attorney in fact and agent or his substitute, may lawfully do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, I have hereunto set my hand this 28^th day of February, 2014.

GREAT-WEST LIFE & ANNUITY INSURANCE COMPANY

POWER OF ATTORNEY

KNOW ALL MEN BY THESE PRESENTS, that I, John Bernbach, member of the Board of Directors of Great-West Life & Annuity Insurance Company, a Colorado corporation, do hereby constitute and appoint R.G. Schultz and B.A. Byrne, and each of them, as my true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for me and in my name, place and stead, in any and all capacities to execute registration statements of the SecureFoundation® Group Fixed Deferred Annuity Smart Future Certificate of Great-West Life & Annuity Insurance Company on Form S-1, or any successor form of registration statement of the Securities and Exchange Commission, filed under the Securities Act of 1933, and any and all amendments thereto, with all exhibits, instruments, and other documents necessary or appropriate in connection therewith, and to file with the Securities and Exchange Commission or any other regulatory authority as may be necessary or desirable, hereby ratifying and confirming all and every act and thing requisite to all intents and purposes that said attorney in fact and agent or his substitute, may lawfully do or cause to be done by virtue hereof.

IN WITNESS WHEREOF, I have hereunto set my hand this 28^th day of February, 2014.