Capital and Regulatory Matters (Tables)

3 Months Ended

Mar. 31, 2018

The following tables present actual and required capital ratios as of March 31, 2018 and December 31, 2017 for Cullen/Frost and Frost Bank under the Basel III Capital Rules. The minimum required capital amounts presented include the minimum required capital levels as of March 31, 2018 and December 31, 2017 based on the phase-in provisions of the Basel III Capital Rules and the minimum required capital levels as of January 1, 2019 when the Basel III Capital Rules have been fully phased-in. Capital levels required to be considered well capitalized are based upon prompt corrective action regulations, as amended to reflect the changes under the Basel III Capital Rules. See the 2017 Form 10-K for a more detailed discussion of the Basel III Capital Rules.



	Actual				Minimum Capital Required - Basel III Phase-In Schedule				Minimum Capital Required - Basel III Fully Phased-In				Required to be Considered Well Capitalized
	Capital Amount		Ratio		Capital Amount		Ratio		Capital Amount		Ratio		Capital Amount		Ratio
March 31, 2018
Common Equity Tier 1 to Risk-Weighted Assets
Cullen/Frost	$	2,504,319	12.69	%	$	1,258,491	6.375	%	$	1,381,873	7.00	%	$	1,283,167	6.50	%
Frost Bank	2,560,828		13.00		1,255,352		6.375		1,378,426		7.00		1,279,967		6.50
Tier 1 Capital to Risk-Weighted Assets
Cullen/Frost	2,648,805		13.42		1,554,607		7.875		1,677,988		8.50		1,579,283		8.00
Frost Bank	2,560,828		13.00		1,550,729		7.875		1,673,803		8.50		1,575,344		8.00
Total Capital to Risk-Weighted Assets
Cullen/Frost	3,032,190		15.36		1,949,427		9.875		2,072,809		10.50		1,974,104		10.00
Frost Bank	2,711,213		13.77		1,944,565		9.875		2,067,639		10.50		1,969,180		10.00
Leverage Ratio
Cullen/Frost	2,648,805		8.62		1,228,567		4.00		1,228,567		4.00		1,535,709		5.00
Frost Bank	2,560,828		8.34		1,227,539		4.00		1,227,539		4.00		1,534,424		5.00



	Actual				Minimum Capital Required - Basel III Phase-In Schedule				Minimum Capital Required - Basel III Fully Phased-In				Required to be Considered Well Capitalized
	Capital Amount		Ratio		Capital Amount		Ratio		Capital Amount		Ratio		Capital Amount		Ratio
December 31, 2017
Common Equity Tier 1 to Risk-Weighted Assets
Cullen/Frost	$	2,426,048	12.42	%	$	1,123,430	5.75	%	$	1,367,583	7.00	%	$	1,269,965	6.50	%
Frost Bank	2,518,999		12.92		1,120,663		5.75		1,364,214		7.00		1,266,836		6.50
Tier 1 Capital to Risk-Weighted Assets
Cullen/Frost	2,570,534		13.16		1,416,499		7.25		1,660,637		8.50		1,563,033		8.00
Frost Bank	2,518,999		12.92		1,413,010		7.25		1,656,546		8.50		1,559,183		8.00
Total Capital to Risk-Weighted Assets
Cullen/Frost	2,959,326		15.15		1,807,257		9.25		2,051,375		10.50		1,953,792		10.00
Frost Bank	2,674,791		13.72		1,802,805		9.25		2,046,321		10.50		1,948,979		10.00
Leverage Ratio
Cullen/Frost	2,570,534		8.46		1,215,227		4.00		1,215,186		4.00		1,519,034		5.00
Frost Bank	2,518,999		8.30		1,214,295		4.00		1,214,254		4.00		1,517,869		5.00