Due to road closures on Friday, September 5, 2025, the Polk City lobby will be closed and the drive up will only be accessible by walk up.

Attention Deposit Account Customers:

Effective September 2, 2025, you will no longer be able to use your GSB debit/ATM card to deposit at non-GSB owned ATMs. You will still be able to deposit at the GSB owned ATMs located at each of our four (4) branches. You can also conveniently deposit checks via Mobile Deposit through our mobile app. If you are not currently set up for Online or Mobile Banking, stop in or contact any of our branches and a personal banker will assist you.

To learn more about how to use Mobile Deposit, visit our Online Banking Education Center.

We understand that this may change how you deposit, however, this decision has been made due to the increasing level of risk associated with check fraud deposits occurring at ATMs.

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Grinnell State Bank Branch Locations & Hours

LOCATED DOWNTOWN IN THE HEART OF THE GRINNELL COMMUNITY

Grinnell Branch

ADDRESS

814 4th Avenue
PO Box 744
Grinnell, IA 50112

HOURS

Monday – Thursday 8:30am – 4:30pm
Friday 8:30am – 5:00pm
Saturday Closed*

DRIVE-UP HOURS

Monday – Friday 8:00am – 5:00pm
Saturday Closed*

DRIVE-UP ATM

24 Hour ATM located in the alley.

HOLIDAY HOURS

PHONE

Grinnell (641) 236-3174
Toll Free (800) 236-3187
Fax (641) 236-4329
Lost/Stolen Debit Cards (800) 383-8000

Grinnell Wealth Management (641) 260-2GWM (2496)

*Customer Service Support is available by phone on Saturday mornings from 9:00am – 12:00pm via the Toll Free Number.

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LOCATED IN THE DOWNTOWN SQUARE OF MARENGO

Marengo Branch

ADDRESS

1101 Court Avenue
PO Box 168
Marengo, IA 52301

HOURS

Monday – Thursday 8:30am – 4:00pm
Friday 8:30am – 5:00pm
Saturday Closed*

DRIVE-UP HOURS

Monday – Friday 8:00am – 5:00pm
Saturday Closed*

INDOOR ATM

24 Hour ATM located in the bank entryway.

HOLIDAY HOURS

PHONE

Marengo (319) 642-5511
Fax (319) 642-1111
Toll Free (800) 236-3187
Insurance (319) 642-5514
Lost/Stolen Debit Cards (800) 383-8000

*Customer Service Support is available by phone on Saturday mornings from 9:00am – 12:00pm via the Toll Free Number.

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LOCATED NORTH OF INTERSTATE 80 ON MERLE HAY ROAD

Johnston Branch

ADDRESS

5601 Merle Hay Road
PO Box 200
Johnston, IA 50131

HOURS

Monday – Friday 9:00am – 4:30pm
Saturday Closed*

DRIVE-UP HOURS

Monday – Friday 8:30am – 5:00pm
Saturday Closed*

DRIVE-UP ATM

24 Hour ATM located in the drive-up.

HOLIDAY HOURS

PHONE

Johnston (515) 278-6300
Toll Free (800) 236-3187
Fax (515) 278-6370
Lost/Stolen Debit Cards (800) 383-8000

*Customer Service Support is available by phone on Saturday mornings from 9:00am – 12:00pm via the Toll Free Number.

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LOCATED IN THE HEART OF POLK CITY

Polk City Branch

ADDRESS

205 Broadway Street
PO Box 79
Polk City, IA 50226

HOURS

Monday – Friday 9:00am – 4:30pm
Saturday Closed*

DRIVE-UP HOURS

Monday – Friday 8:30am – 5:00pm
Saturday Closed*

DRIVE-UP ATM

24 Hour ATM located at the drive-up entrance.

HOLIDAY HOURS

PHONE

Polk City (515) 984-6211
Toll Free (800) 236-3187
Fax (515) 984-6986
Lost/Stolen Debit Cards (800) 383-8000

*Customer Service Support is available by phone on Saturday mornings from 9:00am – 12:00pm via the Toll Free Number.

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2025 Holiday Schedule

Martin Luther King Jr Day

Monday | January 20, 2025

CLOSED

Any transactions after closing Friday, January 17 will post
to your account on Tuesday, January 21.

Presidents Day

Monday | February 17, 2025

CLOSED 

Any transactions after closing Friday, February 14 will post
to your account on Tuesday, February 18.

Memorial Day

Monday | May 26, 2025

CLOSED

Any transactions after closing Friday, May 23 will post
to your account on Tuesday, May 27.

Juneteenth

Thursday | June 19, 2025

Open Normal Hours | Non-Processing

Any transactions after closing Wednesday, June 18 will post
to your account on Friday, June 20.

Independence Day

Friday | July 4, 2025

CLOSED 

Any transactions after closing Thursday, July 3 will post
to your account on Monday, July 7.

Labor Day

Monday | September 1, 2025

CLOSED

Any transactions after closing Friday, August 29 will post
to your account on Tuesday, September 2.

Columbus Day

Monday | October 13, 2025

CLOSED

Any transactions after closing Friday, October 10 will post
to your account on Tuesday, October 14.

Veterans Day

Tuesday | November 11, 2025

CLOSED

Any transactions after closing Monday, November 10 will post
to your account on Wednesday, November 12.

Thanksgiving

Thursday | November 27, 2025

CLOSED

Any transactions after closing Wednesday, November 26 will

post to your account on Friday, November 28.

Black Friday

Friday | November 28, 2025

Open until 12PM

Any transactions after closing Friday, November 28 will post
to your account on Monday, December 1.

Christmas Eve

Wednesday | December 24, 2025

Open until 12PM

Any transactions after closing Wednesday, December 24 will post
to your account on Friday, December 26.

Christmas Day

Thursday | December 25, 2025

CLOSED

Any transactions after closing Wednesday, December 24 will post
to your account on Friday, December 26.

New Years Eve

Wednesday | December 31, 2025

Lobby open until 12PM | Drive-Up open until 3PM

Any transactions after closing Wednesday, December 31 will post
to your account on Friday, January 2.

New Years Day

Thursday | January 1, 2026

CLOSED

Any transactions after closing Wednesday, December 31 will post
to your account on Friday, January 2, 2026.

BENEFITS OF YOUR ACCOUNT

Bringing the Bank to you

We want to make banking easy for you with 24/7 access to your accounts and convenient access to services. Have 24/7 access to all of the following without having to step foot in the bank:

Your Current Accounts

Mobile App with Mobile Deposit, Bill Pay, Internal Account Transfers & more

Fee-Free Shazam Privileged Status ATMs

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