Exhibit 99.1

Citizens Financial Group, Inc. (the “Company”) supplemental information to reflect changes to disclosure of (a) net interest income and net interest margin and (b) noninterest expense for full year and quarterly periods of 2018 and 2017, respectively.

Net interest income (NII) and Net interest margin (NIM):

$s in millions	4Q18					3Q18					2Q18					1Q18					FY2018
	NII		NIM			NII		NIM			NII		NIM			NII		NIM			NII		NIM
Prior methodology(1)	$	1,172		3.22	%	$	1,148		3.19	%	$	1,121		3.18	%	$	1,091		3.16	%	$	4,532		3.19	%
New methodology impact(1)		—		0.01			—		0.01			—		0.02			—		0.03			—		0.02
Revised NIM				3.23					3.20					3.20					3.19					3.21
FTE adjustment		5		0.02			6		0.02			6		0.02			5		0.02			22		0.01
FTE basis(2)	$	1,177		3.25	%	$	1,154		3.22	%	$	1,127		3.22	%	$	1,096		3.21	%	$	4,554		3.22	%

	4Q17					3Q17					2Q17					1Q17					FY2017
	NII		NIM			NII		NIM			NII		NIM			NII		NIM			NII		NIM
Prior methodology(1)	$	1,080		3.08	%	$	1,062		3.05	%	$	1,026		2.97	%	$	1,005		2.96	%	$	4,173		3.02	%
New methodology impact(1)		—		0.02			—		0.02			—		0.02			—		0.03			—		0.02
Revised NIM				3.10					3.07					2.99					2.99					3.04
FTE adjustment		10		0.02			10		0.02			9		0.03			9		0.02			38		0.02
FTE basis(2)	$	1,090		3.12	%	$	1,072		3.09	%	$	1,035		3.02	%	$	1,014		3.01	%	$	4,211		3.06	%

1) Consistent with its understanding of general peer practice, the Company will simplify the calculation of its reported NIM to equal net interest income, annualized based on the number of days in the period, divided by average total interest-earning assets for the period. Under the Company’s prior methodology, NIM was calculated using the difference between the annualized yield on average total interest-earning assets and average total interest-bearing liabilities for the period.

2) Net interest income and net interest margin are presented on a fully taxable-equivalent basis using the federal statutory tax rate of 21% for the 2018 periods presented and 35% for the 2017 periods presented. Interest income earned on certain assets is either completely or partially exempt from federal income tax. Because the federal income tax benefit on tax-exempt assets is realized in income tax expense, it typically results in lower interest-earning asset yields on these assets, relative to taxable assets. In the Company’s fully taxable-equivalent presentation of net interest income and net interest margin, interest income on tax-exempt assets is increased using the federal statutory tax rate to make them fully tax-equivalent to interest income earned on taxable assets.

Note – Amounts may not sum due to rounding.

Noninterest expense – new disclosure format:

$s in millions	4Q18		3Q18		2Q18		1Q18		FY2018
Salaries and employee benefits	$	483	$	474	$	453	$	470	$	1,880
Equipment and software expense		124		117		110		113		464
Outside services		135		107		106		99		447
Occupancy		92		81		79		81		333
Other operating expense		117		131		127		120		495
Total noninterest expense	$	951	$	910	$	875	$	883	$	3,619

	4Q17		3Q17		2Q17		1Q17		FY2017
Salaries and employee benefits	$	450	$	438	$	432	$	446	$	1,766
Equipment and software expense		113		110		109		111		443
Outside services		118		99		96		91		404
Occupancy		80		78		79		82		319
Other operating expense		137		133		148		124		542
Total noninterest expense	$	898	$	858	$	864	$	854	$	3,474

Noninterest expense – prior disclosure format:

$s in millions	4Q18		3Q18		2Q18		1Q18		FY2018
Salaries and employee benefits	$	483	$	474	$	453	$	470	$	1,880
Equipment and software expense		135		107		106		99		447
Outside services		92		81		79		81		333
Occupancy		74		70		64		67		275
Amortization of software		50		47		46		46		189
Other operating expense		117		131		127		120		495
Total noninterest expense	$	951	$	910	$	875	$	883	$	3,619

	4Q17		3Q17		2Q17		1Q17		FY2017
Salaries and employee benefits	$	450	$	438	$	432	$	446	$	1,766
Equipment and software expense		118		99		96		91		404
Outside services		80		78		79		82		319
Occupancy		67		65		64		67		263
Amortization of software		46		45		45		44		180
Other operating expense		137		133		148		124		542
Total noninterest expense	$	898	$	858	$	864	$	854	$	3,474