Exhibit 99.1

OTTAWA BANCORP, INC.

Announces First Quarter 2018 Results

Ottawa, Illinois – April 27, 2018 - Ottawa Bancorp, Inc. (the “Company”) (Nasdaq CM: OTTW), the holding company for Ottawa Savings Bank, FSB (the “Bank”), announced net income of $0.5 million, or $0.15 per basic and diluted common share for the three months ended March 31, 2018, compared to net income of $0.4 million, or $0.11 per basic and diluted common share for the three months ended March 31, 2017. During the first quarter of 2018 the Company continued to experience strong loan demand and a decrease in non-performing loans. Non-performing loans decreased from $1.6 million at December 31, 2017 to $1.3 million at March 31, 2018, which in addition to loan growth, improved the ratio of non-performing loans to gross loans from 0.75% at December 31, 2017 to 0.56% at March 31, 2018. Additionally, through March 31, 2018, the Company has repurchased a total of 67,905 shares of its common stock at an average price of $14.18 per share as part of the stock repurchase program announced on November 15, 2017.

Comparison of Results of Operations for the Three Months Ended March 31, 2018 and March 31, 2017

Net income for the three months ended March 31, 2018 was $0.5 million compared to net income of $0.4 million for the three months ended March 31, 2017. The increase in net income of $0.1 million or 34.2%, was primarily attributed to an increase in net interest income after provision for loan losses of $0.1 million and an increase in total other income of $0.1 million, partially off-set by an increase in total other expenses of $0.1 million.

Net interest income increased by $0.2 million, or 8.2%, to $2.2 million for the three months ended March 31, 2018, from $2.0 million for the three months ended March 31, 2017. Interest and dividend income increased $0.3 million, or 14.9%, primarily due to an increase in the average balances of interest-earning assets of $29.6 million. The increase in net interest income was partially off-set by an increase in interest expense as the average cost of funds increased 27 basis points to 0.78% for the three months ended March 31, 2018. The net interest margin decreased 5.0% during the three months ended March 31, 2018 to 3.63% from 3.82%.

We recorded a provision for loan losses of approximately $0.1 million for both of the three-month periods ended March 31, 2018 and 2017. The allowance for loan losses was $2.6 million, or 1.15% of total gross loans at March 31, 2018 compared to $2.2 million, or 1.26% of gross loans at March 31, 2017. Net charge-offs during the first quarter of 2018 were approximately $27,000 compared to $0.2 million during the first quarter of 2017. General reserves were higher at March 31, 2018, when compared to March 31, 2017, as the balances in all loan categories increased during the twelve months ended March 31, 2018. These increases to the allowance were partially off-set by improvements in historical loss levels and changes in qualitative factors during the twelve months ended March 31, 2018, as compared to the same period ended March 31, 2017. Additionally, specific reserves as of March 31, 2018 were lower than they were as of March 31, 2017.

Total other income increased $0.1 million, to $0.5 million for the three months ended March 31, 2018, as compared to $0.4 million for the three months ended March 31, 2017. The increase was primarily due to higher revenues related to mortgage banking activity and an increase in the gain on sale of foreclosed real estate.

Total other expense increased $0.1 million, or 6.8%, to $1.9 million for the three months ended March 31, 2018, as compared to $1.8 million for the three months ended March 31, 2017.  The increase was primarily due to increased loan expenses, higher data processing expense, and higher other expenses.

We recorded income tax expense of approximately $0.2 million for both of the three-month periods ended March 31, 2018 and 2017.

Comparison of Financial Condition at March 31, 2018 and December 31, 2017

Total consolidated assets as of March 31, 2018 were $268.0 million, an increase of $12.6 million, or 4.9%, from $255.4 million at December 31, 2017.  The increase was primarily due to an increase of $13.2 million in the net loan portfolio, off-set by decreases in securities available for sale of $0.6 million and decreases in cash and cash equivalents of $0.6 million.

Cash and cash equivalents decreased $0.6 million, or 15.5%, to $3.2 million at March 31, 2018 from $3.8 million at December 31, 2017. The decrease in cash and cash equivalents was primarily a result of cash used in investing activities of $13.7 million exceeding cash provided by financing activities of $11.7 million and cash provided by operating activities of $1.4 million.

Securities available for sale decreased $0.6 million, or 2.3%, to $25.4 million at March 31, 2018 from $26.0 million at December 31, 2017, as paydowns, calls, and maturities exceeded new securities purchases.

Net loans increased by $13.2 million, or 6.4% to $220.2 million at March 31, 2018 compared to $207.0 million at December 31, 2017 primarily as a result of a $6.2 million increase in one-to-four family loans, a $2.3 million increase in purchased auto loans, a $2.2 million increase in consumer direct loans and a $1.6 million increase in non-residential real estate loans. The Company also experienced growth in all other loan categories during the three months ended March 31, 2018. The increases were slightly off-set by an increase in the allowance for loan losses of $0.1 million.

Total deposits increased $14.9 million, or 8.2%, to $197.7 million at March 31, 2018 from $182.8 million at December 31, 2017. At March 31, 2018 checking accounts increased by $6.2 million, savings accounts increased by $0.8 million and certificates of deposit increased by $8.1 million as compared to December 31, 2017. The increases were off-set by a decrease in money market accounts of $0.2 million.

FHLB advances decreased $2.2 million, or 14.9% to $12.9 million at March 31, 2018 compared to $15.1 million at December 31, 2017.

Stockholders’ equity decreased approximately $0.6 million, or 1.2% to $51.3 million at March 31, 2018 from $51.9 million at December 31, 2017. The decrease reflects $0.7 million to repurchase and cancel 50,305 outstanding shares, $0.4 million in declared dividends and a decrease in other comprehensive income of $0.2 million related to a decrease in the fair value of securities available for sale. These decreases were partially off-set by net income of $0.5 million for the three months ended March 31, 2018 and proceeds from stock options exercised and the allocation of ESOP shares totaling approximately $0.1 million.

About Ottawa Bancorp, Inc.

Ottawa Bancorp, Inc. is the holding company for Ottawa Savings Bank, FSB which provides various financial services to individual and corporate customers in the United States. The Bank offers various deposit accounts, including checking, money market, regular savings, club savings, certificates of deposit, and various retirement accounts. Its loan portfolio includes one-to-four family residential mortgage, multi-family and non-residential real estate, commercial, and construction loans as well as auto loans and home equity lines of credit. Ottawa Savings Bank, FSB was founded in 1871 and is headquartered in Ottawa, Illinois. For more information about the Company and the Bank, please visit www.ottawasavings.com.

Safe-Harbor

This news release contains forward-looking statements within the meaning of the federal securities laws. Statements in this release that are not strictly historical are forward-looking and are based upon current expectations that may differ materially from actual results. These forward-looking statements, identified by words such as “will,” “expected,” “believe,” and “prospects,” involve risks and uncertainties that could cause actual results to differ materially from those anticipated by the statements made herein. These risks and uncertainties involve general economic trends and changes in interest rates, increased competition, changes in consumer demand for financial services, the possibility of unforeseen events affecting the industry generally, the uncertainties associated with newly developed or acquired operations, and market disruptions. Ottawa Bancorp, Inc. undertakes no obligation to release revisions to these forward-looking statements publicly to reflect events or circumstances after the date hereof or to reflect the occurrence of unforeseen events, except as required to be reported under the rules and regulations of the Securities and Exchange Commission.