CNBKA Century BanCorp Inc

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 11-K

For the fiscal year ended December 31, 2020

For the transition period from                      to                     

Commission file number 0-15752

SBERA 401(k) PLAN AS ADOPTED BY CENTURY BANCORP, INC.

(Full Title of the Plan)

CENTURY BANCORP, INC.

(Issuer of the securities held pursuant to the Plan)

400 Mystic Avenue

Medford, MA 02155

(Address of principal executive offices)

The Plan is subject to the Employee Retirement Income Security Act of 1974 (ERISA). Therefore, in lieu of the requirements of Items 1-3 of Form 11-K, the financial statements and supplemental schedule of the Plan for the two fiscal years ended December 31, 2020 and 2019, have been prepared in accordance with the financial reporting requirements of ERISA, are attached hereto.

SBERA 401(k) PLAN AS ADOPTED BY

CENTURY BANCORP, INC.

FINANCIAL STATEMENTS

AND SUPPLEMENTAL INFORMATION

As of December 31, 2020 and 2019

For the Year Ended December 31, 2020

SBERA 401(k) PLAN AS ADOPTED BY CENTURY BANCORP, INC.

TABLE OF CONTENTS

Schedules required by section 2520.103-10 of the Department of Labor’s Rules and Regulations for Reporting and Disclosure under ERISA, other than those listed above, are omitted because of the absence of conditions under which they are required.

SBERA 401(k) PLAN AS ADOPTED BY CENTURY BANCORP, INC.

See notes to financial statements.

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SBERA 401(k) PLAN AS ADOPTED BY CENTURY BANCORP, INC.

STATEMENT OF CHANGES IN NET ASSETS AVAILABLE FOR BENEFITS

See notes to financial statements.

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SBERA 401(k) PLAN AS ADOPTED BY CENTURY BANCORP, INC.

NOTES TO FINANCIAL STATEMENTS

The following brief description of the SBERA 401(k) Plan as adopted by Century Bancorp, Inc. (the Plan) is provided for general information purposes only. Participants should refer to the plan agreement for more complete information.

General –

The Plan is a defined contribution plan covering substantially all employees of Century Bancorp (the Bank). The Plan is subject to the provisions of the Employee Retirement Income Security Act of 1974, as amended (ERISA).

The Plan is administered by Savings Banks Employees Retirement Association (“SBERA”) which has overall responsibility for the operation and administration of the Plan. An Investment Committee consisting of the Plan’s trustees determines the appropriateness of the Plan’s investment offerings and monitors investment performance.

The Plan participates in the SBERA Common Collective Trust (the Trust). Under the Trust agreement, the Plan owns a portion of the net assets of the Trust, which represents its interest in the Trust. Within the Trust, each of the member banks’ plan assets are jointly invested and the return on the assets is allocated to each plan based on the percentage of ownership each plan has in the Trust’s net assets. Contributions made to and benefits paid from the Trust for the Plan result in increases or decreases in the Plan’s ownership percentage in the net assets of the Trust.

Eligibility Requirements –

To become eligible for participation, an employee must have reached 21 years of age.

Contributions –

Each year, participants may contribute to the Plan a percentage of their annual compensation, on a pre-tax or after-tax “Roth” basis, as defined in the Plan, up to 75% of eligible compensation subject to the Internal Revenue Code (IRC) limitations. Participants who have attained age 50 before the end of the plan year are also eligible to make catch-up contributions. Participants may also contribute amounts representing distributions from other qualified plans or defined contribution plans (rollovers). Participants direct the investment of their contributions into various investment options offered by the Plan. New employees as well as employees deferring less than 3% of compensation will be automatically enrolled in the Plan with a pre-tax deferral of 3% of compensation, unless they opt out of participating or make an affirmative election.

The Bank may elect to make a discretionary matching contribution to eligible participants, as defined in the plan agreement. For the year ended December 31, 2020, the Bank contributed a matching contribution of 33% of participant’s deferrals up to 6% of eligible compensation for a maximum matching contribution of 2%. Total discretionary matching contributions made by the Bank to the Plan were $529,245 for the year ended December 31, 2020. Contributions are subject to certain IRC limitations. The Bank may also elect to make additional discretionary non-elective contributions. The Bank did not make any additional discretionary non-elective contributions for the year ended December 31, 2020.

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SBERA 401(k) PLAN AS ADOPTED BY CENTURY BANCORP, INC.

NOTES TO FINANCIAL STATEMENTS

Participant Accounts –

Each participant’s account is credited with the participant’s contribution, the Bank’s contributions and an allocation of Plan earnings. Allocations are based on the participant’s earnings, account balances, or specific participant transactions, as defined. The benefit to which a participant is entitled is the benefit that can be provided from the participant’s vested account.

Investments –

The Plan currently offers a variety of unitized funds comprised of investments held in the Trust.

Notes Receivable from Participants –

Participants may borrow from their fund accounts a minimum of $1,000 up to a maximum equal to the lesser of $50,000 or 50% of their vested account balance. Notes are required to be repaid within 5 years unless the note is to be used for the purchase of a primary residence in which case the note may be repaid within a period of no more than 20 years. Participants may have up to 2 loans outstanding at any time. The notes are secured by the balance in the participant’s account and bear interest at a rate ranging from 4.25% to 6.50%. The note interest rate is set at the prime rate as published by the Wall Street Journal plus 1%. Principal and interest is paid ratably through payroll deductions.

Payment of Benefits –

Upon termination of service, retirement, disability or death, a participant may elect to receive an amount equal to the value of the participant’s vested interest in his or her account in a lump-sum amount, installment payments or partial payments. In-service withdrawals from the participant’s account are available upon reaching age 59¹⁄₂. A participant may withdraw from their rollover account at any time. If a participant’s vested account balance is $1,000 or less, the Plan administrator can distribute the entire balance in a lump-sum amount. A participant may take a distribution from the Plan upon demonstration to the plan administrator that the participant is suffering from “hardship”, as defined in the plan document.

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SBERA 401(k) PLAN AS ADOPTED BY CENTURY BANCORP, INC.

NOTES TO FINANCIAL STATEMENTS

Payment of Benefits (Continued) –

On December 20, 2019, the Setting Every Community Up for Retirement Enhancement (SECURE) Act of 2019 was signed into law. Under the SECURE Act, the age requirement for minimum distributions was raised to 72 from 70 ¹⁄₂, for any participant who turned 70 ¹⁄₂ on or after January 1, 2020.

On January 1, 2020, certain administrative defaults for the Plan were updated through a Plan amendment to be in accordance with final regulations of the Bipartisan Budget Act of 2018 with regard to the hardship distribution rules applicable to 401(k) plans. These changes included (1) removal of the 6 month deferral suspension, (2) removal of the requirement for a participant to first take available plan loans prior to a hardship withdrawal, (3) allowance of earnings on deferrals to be included in the hardship calculation, and (4) updating of hardship distribution forms to reflect the participant’s representation of hardship need, expanded list of deemed hardship events, and clarification of casualty loss definition.

CARES Act -

On March 27, 2020, Congress passed the Coronavirus Aid, Relief, and Economic Security (CARES) Act. The CARES Act, among other things, includes several relief provisions available to tax-qualified retirement plans and their participants. The provisions of the CARES Act may be effective and operationalized immediately, prior to amending the Plan document. Plan management evaluated the relief provisions available to qualified plan participants under the CARES Act and implemented the following provisions:

Forfeitures –

At December 31, 2020 and 2019, forfeited nonvested accounts totaled $125 and $509, respectively. These accounts may be used to offset future Bank contributions, pay eligible plan expenses or be reallocated to participants. Also, in 2020, employer contributions were reduced by $26,238 from forfeited nonvested accounts.

Administrative Expenses –

Administrative expenses including investment related fees are paid directly by the Trust and are reflected in the Plan’s share of the Trust net investment activity. In addition, included within the Plan’s interest in the Trust’s net investment income, in the accompanying Statement of Changes in Net Assets Available for Benefits, are certain investment related expenses included in the unrealized appreciation in fair value of investments.

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SBERA 401(k) PLAN AS ADOPTED BY CENTURY BANCORP, INC.

NOTES TO FINANCIAL STATEMENTS

The following are significant accounting policies followed by the Plan:

Basis of Accounting –

The financial statements of the Plan are prepared on the accrual basis of accounting.

Use of Estimates –

The preparation of financial statements, in accordance with accounting principles generally accepted in the United States of America requires Plan management to make estimates and assumptions that affect the reported amounts of assets and liabilities and changes therein, and disclosure of contingent assets and liabilities. Actual results could differ from those estimates.

Investment Valuation and Income Recognition –

The Plan’s interest in the Trust is reported at fair value. Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The Plan’s Investment Committee determines the Plan’s valuation policies utilizing information provided by its investment managers and custodians.

Purchases and sales of securities are recorded on a trade-date basis. Interest income is recorded on the accrual basis. Dividends are recorded on the ex-dividend date. Net investment income includes interest and dividend income and the Plan’s gains and losses on investments bought and sold as well as held during the year. The Plan’s sole investment at December 31, 2020 and 2019 is its interest in the Trust. Consequently, it recognizes investment income based on its share of the income and loss derived from the underlying assets of the Trust.

Notes Receivable from Participants –

Notes receivable from participants are measured at their unpaid principal balance plus any accrued but unpaid interest. Interest income is recorded on the accrual basis. Related fees are charged against participant accounts when incurred. No allowance for credit losses has been recorded as of December 31, 2020 and 2019. Delinquent notes receivable from participants, if applicable, are reclassified as distributions based upon the terms of the Plan document. The amounts reported on the accompanying Statements of Net Assets Available for Benefits as of December 31, 2020 and 2019 represent the Plan’s portion of notes receivable from participants recorded by the Trust.

Payment of Benefits –

Benefit payments to participants are recorded when paid.

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SBERA 401(k) PLAN AS ADOPTED BY CENTURY BANCORP, INC.

NOTES TO FINANCIAL STATEMENTS

Risks and Uncertainties –

The Plan, through its investment in the Trust, invests in various investment securities. Investment securities are exposed to various risks such as interest rate, market, and credit risks. Due to the level of risk associated with certain investment securities, it is at least reasonably possible that changes in the values of investment securities will occur in the near term and that such change could materially affect the amounts reported in the Statements of Net Assets Available for Benefits.

As a result of the continued spread of the COVID-19 coronavirus, economic uncertainties have arisen which have triggered volatility in the financial markets. However, because the values of the Plan’s individual investments have and will fluctuate in response to changing market conditions, the amount of losses that will be recognized in subsequent periods, if any, cannot be predicted.

Date of Management’s Review –

The Plan has evaluated subsequent events through the date the financial statements were issued.

On April 7, 2021, the stock holding company for the Bank announced they have entered into a merger agreement with another banking institution. The acquisition is expected to close in the fourth quarter of 2021, subject to certain conditions. Upon closing, the Bank will merge into the other banking institution’s operations. Plan management is currently evaluating the impact of the merger on the Plan.

The framework for measuring fair value provides a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (level 1) and the lowest priority to unobservable inputs (level 3). The three levels of the fair value hierarchy under FASB ASC 820 are described as follows:

Level 1: Inputs to the valuation methodology are unadjusted quoted prices for identical assets or liabilities in active markets that the Trust has the ability to access.

Level 2: Inputs to the valuation methodology include: quoted prices for similar assets or liabilities in active markets; quoted prices for identical or similar assets or liabilities in inactive markets; inputs other than quoted prices that are observable for the asset or liability; or inputs that are derived principally from or corroborated by observable market data by correlation or other means. If the asset or liability has a specified (contractual) term, the level 2 input must be observable for substantially the full term of the asset or liability.

Level 3: Inputs to the valuation methodology are unobservable and significant to the fair value measurement.

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SBERA 401(k) PLAN AS ADOPTED BY CENTURY BANCORP, INC.

NOTES TO FINANCIAL STATEMENTS

The asset or liability’s fair value measurement level within the fair value hierarchy is based on the lowest level of any input that is significant to the fair value measurement. Valuation techniques maximize the use of relevant observable inputs and minimize the use of unobservable inputs.

Certain investments are measured using the net asset value (NAV) as a practical expedient to estimate fair value. The NAV is based on the fair value of the underlying investments held by the fund less its liabilities. These investments measured using the NAV practical expedient in Fair Value Measurement (Topic 820) are exempt from categorization in the fair value hierarchy.

Following is a description of the valuation methodologies used for assets measured at fair value by the Trust. There have been no changes in these methodologies used by the Trust at December 31, 2020 and 2019.

Certificates of deposit:

Certificates of deposit are measured at amortized cost, which approximates fair value.

Collective funds:

Valued at either the closing price reported on the active market on which the individual securities are traded or valued at the NAV of units of a collective trust. The NAV, as provided by the trustee, is used as a practical expedient to estimate fair value or is a readily determinable fair value and is the basis for the current transactions. The NAV is based on the fair value of the underlying investments held by the fund less its liabilities. This practical expedient is not used when it is determined to be probable that the fund will sell the investment for an amount different than the reported NAV. Participant transactions (purchases and sales) may occur daily. Were the Trust to initiate a full redemption of the collective trust, the investment advisor reserves the right to temporarily delay withdrawal from the Trust in order to ensure that securities liquidations will be carried out in an orderly business manner.

Equity securities:

Valued at the closing price reported on the active market on which the individual securities are traded.

Mutual funds:

Valued at the daily closing price as reported by the fund. Mutual funds held by the Trust are open-end mutual funds that are registered with the U.S. Securities and Exchange Commission. These funds are required to publish their daily NAV and to transact at that price. The mutual funds held by the Trust are deemed to be actively traded.

Limited partnerships and hedge funds:

The funds are valued at NAV, without further adjustment, as calculated by the fund’s manager based upon the terms and conditions of the organizational documents of the underlying investments, with further consideration to portfolio risks.

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SBERA 401(k) PLAN AS ADOPTED BY CENTURY BANCORP, INC.

NOTES TO FINANCIAL STATEMENTS

The following tables set forth by level, within the fair value hierarchy, the Trust’s assets at fair value as of December 31, 2020 and 2019. Classification within the fair value hierarchy tables is based upon the lowest level of any input that is significant to the fair value measurement:

There were no transfers to or from Levels 1, 2, and 3 during the years ended December 31, 2020 and 2019.

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SBERA 401(k) PLAN AS ADOPTED BY CENTURY BANCORP, INC.

NOTES TO FINANCIAL STATEMENTS

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SBERA 401(k) PLAN AS ADOPTED BY CENTURY BANCORP, INC.

NOTES TO FINANCIAL STATEMENTS

Investments Measured Using the Net Asset Value per Share Practical Expedient (Continued) –

All of the Plan’s investments are in the Trust, which was established for the investment of assets of the Plan and several other member bank sponsored retirement plans. Each participating retirement plan has a divided interest in the Trust. The assets of the Trust are held by several custodians. The Trust allows for daily redemptions. The Plan does not have any unfunded commitments.

The value of the Plan’s interest in the Trust is based on the beginning of year value of the Plan’s interest in the Trust plus actual contributions and allocated investment income less actual distributions and allocated administrative expenses plus the Plan’s portion of notes receivable from participants held as of the plan year end. At December 31, 2020 and 2019, the Plan’s interest in the Trust was approximately 2.19% and 2.26%, respectively. Investment income and administrative expenses relating to the Trust are allocated to the individual plans based upon average monthly balances invested by each plan.

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SBERA 401(k) PLAN AS ADOPTED BY CENTURY BANCORP, INC.

NOTES TO FINANCIAL STATEMENTS

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SBERA 401(k) PLAN AS ADOPTED BY CENTURY BANCORP, INC.

NOTES TO FINANCIAL STATEMENTS

Although it has not expressed any intent to do so, the Bank has the right under the Plan to discontinue its contributions at any time and to terminate the Plan subject to the provisions of ERISA. In the event of Plan termination, participants will become 100% vested in their accounts.

The SBERA 401(k) Plan as adopted by the Plan is a volume submitter plan. Benefit Plans Administrative Services, LLC maintains the overall volume submitter plan document (master document). Benefit Plans Administrative Services, LLC has applied for and received Internal Revenue Service (IRS) approval of the master document. As of March 31, 2014, a favorable opinion letter has been received by the volume submitter plan sponsor. The Plan’s Administrator and the Plan’s tax counsel believe that the Plan is designed, and is currently being operated, in compliance with the applicable requirements of the IRC. Therefore, no provision for income taxes has been included in the Plan’s financial statements.

Accounting principles generally accepted in the United States of America require plan management to evaluate tax positions taken by the plan and recognize a tax liability if the plan has taken an uncertain position that more likely than not would not be sustained upon examination by the IRS. The Plan is subject to routine audits by taxing jurisdictions; however, there are currently no audits for any tax periods in progress.

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SBERA 401(k) PLAN AS ADOPTED BY CENTURY BANCORP, INC.

NOTES TO FINANCIAL STATEMENTS

Northeast Retirement Services (NRS), by contract with the approval of the Boards of Trustees of SBERA and NRS, provides consulting, recordkeeping and other services in connection with the administration of the 401(k) plan for SBERA. The costs associated with these services are funded by an assessment on each SBERA employer member on a quarterly basis for their proportionate share. In 2020 and 2019, the rate for the 401(k) plan was $929.50 per employer member ($1,229.50 for plans with over 100 participants) per quarter, plus $21.00 per active participant per quarter ($24.00 for member with bank stock), plus an additional 1.25 basis point assessment on assets.

The Plan invests in a common collective trust managed by SBERA, the Trustee of the Plan. Therefore, this qualifies as a party-in-interest transaction. Additionally, the Plan extends notes to participants, who are considered parties-in-interest.

One of the Trust’s investment options that the Plan has elected to allow as an option for plan participants is the plan sponsor’s company stock. Balances of the plan sponsor’s company stock held in the Trust and allocated to participants was $2,954,564 and $3,264,041 as of December 31, 2020 and 2019, respectively.

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SUPPLEMENTAL INFORMATION

SBERA 401(k) PLAN AS ADOPTED BY CENTURY BANCORP, INC.

EIN: 04-2498617, PLAN NUMBER: 002

SCHEDULE H, LINE 4i - SCHEDULE OF ASSETS (HELD AT END OF YEAR)

December 31, 2020

See Report of Independent Registered Public Accounting Firm

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