Exhibit 99.1

NEWS RELEASE

FOR IMMEDIATE RELEASE

CENTURY BANCORP, INC. ANNOUNCES 3RD CONSECUTIVE YEAR OF RECORD

EARNINGS FOR 2012, UP 14%; ASSET GROWTH TO RECORD SIZE OF $3.1 BB; REGULAR

DIVIDEND DECLARED

Medford, MA, January 15, 2013—Century Bancorp, Inc. (NASDAQ:CNBKA) (www.centurybank.com) (“the Company”) today announced record net income of $19,039,000 for the year ended December 31, 2012, or $3.43 per Class A share diluted, an increase of 14.1% compared to net income of $16,693,000, or $3.01 per Class A share diluted, for the same period a year ago. Total assets increased 12.5% from $2.7 billion at December 31, 2011 to $3.1 billion at December 31, 2012. For the quarter ended December 31, 2012, net income totaled $4,778,000, or $0.86 per Class A share diluted, an increase of 14.1% compared to net income of $4,189,000, or $0.76 per Class A share diluted, for the same period a year ago.

Net interest income totaled $62.0 million for the year ended December 31, 2012 compared to $55.3 million for 2011. The 12.0% increase in net interest income for the period is due to an 11.5% increase in the average balances of earning assets, combined with a similar increase in average deposits. The net interest margin increased from 2.48% on a fully taxable equivalent basis in 2011 to 2.51% on the same basis for 2012. This was primarily the result of prepayment penalties that were collected during 2012. Also, interest expense decreased primarily as a result of the continued decline in market rates.

The provision for loan losses decreased by $400,000 from $4.6 million for the year ended December 31, 2011 to $4.2 million, for the year ended December 31, 2012, primarily as a result of changes in the composition of the loan portfolio. The Company capitalized on favorable market conditions for the fourth quarter and year ended December 31, 2012 and realized net gains on sales of investments of $724,000 and $1.8 million, respectively, as compared to $695,000 and $1.9 million, respectively, for the same periods in 2011. FDIC assessments decreased from $2.0 million for the year ended December 31, 2011 to $1.7 million, for the year ended December 31, 2012, primarily as a result of a decrease in the assessment rate, offset somewhat by an increase in the assessment base. The Company’s effective tax rate decreased from 8.5% in 2011 to 6.8% in 2012 primarily as a result of an increase in tax-exempt income.

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At December 31, 2012, total equity was $180.0 million compared to $160.6 million at December 31, 2011. The Company’s equity increased primarily as a result of earnings and other comprehensive income, net of taxes, offset somewhat by dividends paid. The Company’s leverage ratio stood at 6.80% at December 31, 2012, compared to 7.12% at December 31, 2011. This decline in the leverage ratio is due to an increase in assets, offset somewhat, by an increase in stockholders’ equity. Book value as of December 31, 2012 was $32.40 per share compared to $28.98 at December 31, 2011.

The Company’s allowance for loan losses was $19.2 million or 1.73% of loans outstanding at December 31, 2012, compared to $16.6 million or 1.68% of loans outstanding at December 31, 2011. The allowance for loan losses increased despite a decrease in the provision for loan losses due to a lower level of charge-off activity combined with changes in the portfolio composition. Non-performing assets totaled $4.5 million at December 31, 2012, compared to $7.0 million at December 31, 2011.

The Company’s Board of Directors voted a regular quarterly dividend of 12.00 cents ($0.12) per share on the Company’s Class A common stock, and 6.00 cents ($0.06) per share on the Company’s Class B common stock. The dividends were declared payable February 15, 2013 to stockholders of record on February 1, 2013.

The Company, through its subsidiary bank, Century Bank and Trust Company, a state chartered full service commercial bank, operating twenty-five full-service branches in the Greater Boston area, offers a full range of Business, Personal and Institutional Services.

Century Bank and Trust Company is a member of the FDIC and is an Equal Housing Lender.

This press release contains certain “forward-looking statements” with respect to the financial condition, results of operations and business of the Company. Actual results may differ from those contemplated by these statements. The Company wishes to caution readers not to place undue reliance on any forward-looking statements. The Company disclaims any intent or obligation to update publicly any such forward-looking statements, whether in response to new information, future events or otherwise.

Century Bancorp, Inc. and Subsidiaries

Consolidated Comparative Statements of Condition (unaudited)

(in thousands)

Century Bancorp, Inc. and Subsidiaries

Consolidated Comparative Statements of Income (unaudited)

For the Quarter and Year ended December 31, 2012 and 2011

(in thousands)

Century Bancorp, Inc. and Subsidiaries

Consolidated Year-to-Date Average Comparative Statements of Condition (unaudited)

(in thousands)

Century Bancorp, Inc. and Subsidiaries

Consolidated Selected Key Financial Information (unaudited)

(in thousands, except share data)