VOYA VUL-ECV

A FLEXIBLE PREMIUM ADJUSTABLE VARIABLE UNIVERSAL LIFE
INSURANCE POLICY

issued by

Security Life of Denver Insurance Company

and its

Security Life Separate Account L1

Supplement Dated May 19, 2017

This supplement provides up-to-date information about the company and updates and amends your prospectus dated May 1, 2014, and subsequent supplements thereto. Please read it carefully and keep it with your prospectus
for future reference.

______________________________________________________________________________________

NOTICE OF AND IMPORTANT INFORMATION ABOUT AN UPCOMING FUND REORGANIZATION

The following information only affects you if you currently invest in or plan to invest in the Subaccount that corresponds to the VY^® FMR^® Diversified Mid Cap Portfolio.

On November 17, 2016, the Board of Trustees of Voya Investors Trust approved a proposal to reorganize the VY^® FMR^® Diversified Mid Cap Portfolio. Subject to shareholder approval, effective after the close of business on or about July 14, 2017, (the “Reorganization Date”), Class I shares of the VY^® FMR^® Diversified Mid Cap Portfolio (the “Merging Fund”) will reorganize with and into Class I shares of the Voya MidCap Opportunities Portfolio (the “Surviving Fund”).

Voluntary Transfers Before the Reorganization Date. Prior to the Reorganization Date and for 30 days thereafter, you may transfer amounts allocated to the Subaccount that invests in the Merging Fund to any other available Subaccount or to the Guaranteed Interest Division. There will be no charge for any such transfer, and any such transfer will not count as a transfer when imposing any applicable restriction or limit on transfers. See the Transfers section beginning on page 59 of your policy prospectus for information about making Subaccount transfers, including applicable restrictions and limits on transfers.

On the Reorganization Date. On the Reorganization Date, your investment in the Subaccount that invested in the Merging Fund will automatically become an investment in the Subaccount that invests in the Surviving Fund with an equal total net asset value. You will not incur any tax liability because of this automatic reallocation, and your Account Value immediately before the reallocation will equal your Account Value immediately after the reallocation.

Automatic Fund Reallocation After the Reorganization Date. After the Reorganization Date, the Merging Fund will no longer be available through your policy. Unless you provide us with alternative allocation instructions, after the Reorganization Date all allocations directed to the Subaccount that invests in the Merging Fund will be automatically allocated to the Subaccount that invests in the Surviving Fund. See the Transfers section beginning on page 59 of your policy prospectus for information about making fund allocation changes.

Allocation Instructions. You may give us alternative allocation instructions at any time by contacting Customer Service at P.O. Box 5065, Minot, ND 58702-5065, 1-877-253-5050 or www.voyalifecustomerservice.com.

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NOTICE OF AN UPCOMING FUND ADDITION

In connection with the upcoming fund merger involving the VY^® FMR^® Diversified Mid Cap Portfolio referenced above, effective on the Reorganization Date Class I shares of the Voya MidCap Opportunities Portfolio will be added to your policy as a replacement investment option.

Please note the following information about the Voya MidCap Opportunities Portfolio:

Fund Name Investment Adviser/Subadviser	Investment Objective(s)
Voya MidCap Opportunities Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadvisers:  Voya Investment Management Co. LLC	Seeks long-term capital appreciation.

IMPORTANT INFORMATION ABOUT THE FUNDS AVAILABLE THROUGH THE POLICY

The following chart lists the funds that are available through the policy, along with each fund’s investment adviser/subadviser and investment objective. More detailed information about these funds can be found in the current prospectus and Statement of Additional Information for each fund. If you received a summary prospectus for any of the funds available through your policy, you may obtain a full prospectus and other fund information free of charge by either accessing the internet address, calling the telephone number or sending an email request to the email address shown on the front of the fund’s summary prospectus.

There is no assurance that the stated investment objectives of any of the funds will be achieved. Shares of the funds will rise and fall in value and you could lose money by allocating policy value to the subaccounts that invest in the funds. Shares of the funds are not bank deposits and are not guaranteed, endorsed or insured by any financial institution, the Federal Deposit Insurance Corporation or any other government agency.

Fund Name Investment Adviser/Subadviser	Investment Objective(s)
American Funds Insurance Series® – Growth Fund (Class 2)         Investment Adviser:  Capital Research and Management CompanySM	Seeks growth of capital.
American Funds Insurance Series® – Growth - Income Fund (Class 2) Investment Adviser:  Capital Research and Management CompanySM	Seeks long-term growth of capital and income.
American Funds Insurance Series® – International Fund (Class 2) Investment Adviser:  Capital Research and Management CompanySM	Seeks long-term growth of capital.

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Fund Name Investment Adviser/Subadviser	Investment Objective(s)
BlackRock Global Allocation V.I. Fund (Class III) Investment Adviser:  BlackRock Advisors, LLC	Seeks high total investment return.
Fidelity® VIP Contrafund® Portfolio (Service Class) Investment Adviser:  Fidelity Management & Research Company Subadvisers:  FMR Co., Inc. and other investment advisers	Seeks long-term capital appreciation.
Fidelity® VIP Equity-Income Portfolio (Service Class) Investment Adviser:  Fidelity Management & Research Company Subadvisers:  FMR Co., Inc. and other investment advisers	Seeks reasonable income. Also considers the potential for capital appreciation. Seeks to achieve a yield which exceeds the composite yield on the securities comprising the S&P 500® Index.
M Capital Appreciation Fund1 Investment Adviser:  M Financial Investment Advisers, Inc. Subadviser:Frontier Capital Management Company, LLC	Seeks to provide maximum capital appreciation.
M International Equity Fund1 Investment Adviser:  M Financial Investment Advisers, Inc. Subadviser:Northern Cross, LLC	Seeks to provide long-term capital appreciation.
M Large Cap Growth Fund1 Investment Adviser:  M Financial Investment Advisers, Inc. Subadviser:DSM Capital Partners LLC	Seeks to provide long-term capital appreciation.
M Large Cap Value Fund1 Investment Adviser:  M Financial Investment Advisers, Inc. Subadviser:  AJO, LP	Seeks to provide long-term capital appreciation.
Neuberger Berman AMT Socially Responsive Portfolio® (Class I) Investment Adviser:Neuberger Berman Investment Advisers LLC	Seeks long-term growth of capital by investing primarily in securities of companies that meet the Fund’s financial criteria and social policy.

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Fund Name Investment Adviser/Subadviser	Investment Objective(s)
Voya Balanced Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadviser:  Voya Investment Management Co. LLC	Seeks total return consisting of capital appreciation (both realized and unrealized) and current income; the secondary investment objective is long-term capital appreciation.
Voya Global Bond Portfolio (Class S) Investment Adviser:  Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks to maximize total return through a combination of current income and capital appreciation.
Voya Global Equity Portfolio (Class I) Investment Adviser:Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks long-term capital growth and current income.
Voya Global Perspectives® Portfolio (Class I)2 Investment Adviser:Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks total return.
Voya Government Liquid Assets Portfolio (Class S) Investment Adviser:  Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks high level of current income consistent with the preservation of capital and liquidity.
Voya Growth and Income Portfolio (Class I) Investment Adviser:Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks to maximize total return through investments in a diversified portfolio of common stock and securities convertible into common stocks. It is anticipated that capital appreciation and investment income will both be major factors in achieving total return.
Voya Index Plus LargeCap Portfolio (Class I) Investment Adviser:Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks to outperform the total return performance of the S&P 500® Index while maintaining a market level of risk.
Voya Index Plus MidCap Portfolio (Class I) Investment Adviser:Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks to outperform the total return performance of the S&P MidCap 400® Index while maintaining a market level of risk.

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Fund Name Investment Adviser/Subadviser	Investment Objective(s)
Voya Index Plus SmallCap Portfolio (Class I) Investment Adviser:Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks to outperform the total return performance of the S&P SmallCap 600® Index while maintaining a market level of risk.
Voya Intermediate Bond Portfolio (Class I) Investment Adviser:Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks to maximize total return consistent with reasonable risk. The Portfolio seeks its objective through investments in a diversified portfolio consisting primarily of debt securities. It is anticipated that capital appreciation and investment income will both be major factors in achieving total return.
Voya International Index Portfolio (Class S) Investment Adviser:Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks investment results (before fees and expenses) that correspond to the total return (which includes capital appreciation and income) of a widely accepted international index.
Voya Large Cap Growth Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks long-term capital growth.
Voya Large Cap Value Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks long-term growth of capital and current income.
Voya Limited Maturity Bond Portfolio (Class S) Investment Adviser:  Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks highest current income consistent with low risk to principal and liquidity and secondarily, seeks to enhance its total return through capital appreciation when market factors, such as falling interest rates and rising bond prices, indicate that capital appreciation may be available without significant risk to principal.
Voya Multi-Manager Large Cap Core Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadvisers:Columbia Management Investment Advisers, LLC and The London Company of Virginia, LLC d/b/a The London Company	Seeks reasonable income and capital growth.

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Fund Name Investment Adviser/Subadviser	Investment Objective(s)
Voya Retirement Growth Portfolio (Class I)2, 3 Investment Adviser:  Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks a high level of total return (consisting of capital appreciation and income) consistent with a level of risk that can be expected to be greater than that of Voya Retirement Moderate Growth Portfolio.
Voya Retirement Moderate Growth Portfolio (Class I)2, 3 Investment Adviser:  Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks a high level of total return (consisting of capital appreciation and income) consistent with a level of risk that can be expected to be greater than that of Voya Retirement Moderate Portfolio but less than that of Voya Retirement Growth Portfolio.
Voya Retirement Moderate Portfolio (Class I)2, 3 Investment Adviser:  Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks a high level of total return (consisting of capital appreciation and income) consistent with a level of risk that can be expected to be greater than that of Voya Retirement Conservative Portfolio but less than that of Voya Retirement Moderate Growth Portfolio.
Voya RussellTM Large Cap Growth Index Portfolio (Class I) Investment Adviser:Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks investment results (before fees and expenses) that correspond to the total return (which includes capital appreciation and income) of the Russell Top 200® Growth Index.
Voya RussellTM Large Cap Index Portfolio (Class I) Investment Adviser:Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks investment results (before fees and expenses) that correspond to the total return (which includes capital appreciation and income) of the Russell Top 200® Index.
Voya RussellTM Large Cap Value Index Portfolio (Class I) Investment Adviser:Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks investment results (before fees and expenses) that correspond to the total return (which includes capital appreciation and income) of the Russell Top 200® Value Index.
Voya RussellTM Mid Cap Growth Index Portfolio (Class I) Investment Adviser:Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks investment results (before fees and expenses) that correspond to the total return (which includes capital appreciation and income) of the Russell Midcap® Growth Index.
Voya RussellTM Small Cap Index Portfolio (Class I) Investment Adviser:Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks investment results (before fees and expenses) that correspond to the total return (which includes capital appreciation and income) of the Russell 2000® Index.

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Fund Name Investment Adviser/Subadviser	Investment Objective(s)
Voya Small Company Portfolio (Class S) Investment Adviser:Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks growth of capital primarily through investment in a diversified portfolio of common stock of companies with smaller market capitalizations.
Voya SmallCap Opportunities Portfolio (Class I) Investment Adviser:Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks long-term capital appreciation.
Voya Solution Moderately Aggressive Portfolio (Class I)2 Investment Adviser:  Voya Investments, LLC Subadviser:  Voya Investment Management Co. LLC	Seeks to provide capital growth through a diversified asset allocation strategy.
Voya U.S. Bond Index Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks investment results (before fees and expenses) that correspond to the total return (which includes capital appreciation and income) of the Bloomberg Barclays U.S. Aggregate Bond Index.
Voya U.S. Stock Index Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadviser:Voya Investment Management Co. LLC	Seeks total return.
VY® Baron Growth Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadviser:  BAMCO, Inc.	Seeks capital appreciation.
VY® Clarion Global Real Estate Portfolio (Class S) Investment Adviser:  Voya Investments, LLC Subadviser:  CBRE Clarion Securities LLC	Seeks high total return consisting of capital appreciation and current income.
VY® Columbia Small Cap Value II Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadviser:  Columbia Management Investment Advisers, LLC	Seeks long-term growth of capital.

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Fund Name Investment Adviser/Subadviser	Investment Objective(s)
VY® FMR® Diversified Mid Cap Portfolio (Class I)4 Investment Adviser:  Voya Investments, LLC Subadviser:  Fidelity Management & Research Company	Seeks long-term growth of capital.
VY® Invesco Comstock Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadviser:Invesco Advisers, Inc.	Seeks capital growth and income.
VY® Invesco Equity and Income Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadviser:Invesco Advisers, Inc.	Seeks total return consisting of long-term capital appreciation and current income.
VY® Invesco Growth and Income Portfolio (Class S) Investment Adviser:  Voya Investments, LLC Subadviser:Invesco Advisers, Inc.	Seeks long-term growth of capital and income.
VY® JPMorgan Emerging Markets Equity Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadviser:J.P. Morgan Investment Management Inc.	Seeks capital appreciation.
VY® JPMorgan Small Cap Core Equity Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadviser:J.P. Morgan Investment Management Inc.	Seeks capital growth over the long-term.
VY® Oppenheimer Global Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadviser:OppenheimerFunds, Inc.	Seeks capital appreciation.
VY® Pioneer High Yield Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadviser:Pioneer Investment Management, Inc.	Seeks to maximize total return through income and capital appreciation.

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Fund Name Investment Adviser/Subadviser	Investment Objective(s)
VY® T. Rowe Price Capital Appreciation Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadviser:T. Rowe Price Associates, Inc.	Seeks, over the long-term, a high total investment return, consistent with the preservation of capital and with prudent investment risk.
VY® T. Rowe Price Diversified Mid Cap Growth Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadviser:T. Rowe Price Associates, Inc.	Seeks long-term capital appreciation.
VY® T. Rowe Price Equity Income Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadviser:T. Rowe Price Associates, Inc.	Seeks a high level of dividend income as well as long-term growth of capital primarily through investments in stocks.
VY® T. Rowe Price International Stock Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadviser:T. Rowe Price Associates, Inc.	Seeks long-term growth of capital.
VY® Templeton Foreign Equity Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadviser:Templeton Investment Counsel, LLC	Seeks long-term capital growth.

¹This fund is only available through broker/dealers associated with the M Financial Group.

²This fund is structured as a “fund of funds.” A fund structured as a “fund of funds” may have higher fees and expenses than a fund that invests directly in debt and equity securities because it also incurs the fees and expenses of the underlying funds in which it invests. Please refer to the fund prospectus for information about the aggregate annual operating expenses of the fund and its corresponding underlying fund or funds.

³This fund employs a managed volatility strategy. A managed volatility strategy is a strategy that is intended to reduce a fund’s overall volatility and downside risk and, thereby, help us manage the risks associated with providing certain guarantees under the policy. During rising markets, the hedging strategies employed to manage volatility could result in your Separate Account Value rising less than would have been the case if you had been invested in a fund with substantially similar investment objectives, policies and strategies that does not utilize a volatility management strategy. In addition, the cost of these hedging strategies may have a negative impact on investment performance. On the other hand, investing in funds with a managed volatility strategy may be helpful in a declining market with higher market volatility because the hedging strategy will reduce your equity exposure in such circumstances. In such cases, your Separate Account Value may decline less than would have been the case if you had not invested in funds with a managed volatility strategy. There is no guarantee that a managed volatility strategy can achieve or maintain the fund’s optimal risk targets, and the fund may not perform as expected.

⁴FMR^® is a registered service mark of FMR LLC. Used with permission.

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IMPORTANT INFORMATION ABOUT A FUND

CLOSED TO NEW INVESTMENT

The subaccount that invests in the following mutual fund has been closed to new investment:

Fund Name Investment Adviser/Subadviser	Investment Objective(s)
VY® JPMorgan Mid Cap Value Portfolio (Class I) Investment Adviser:  Voya Investments, LLC Subadviser:J.P. Morgan Investment Management Inc.	Seeks growth from capital appreciation.

Policy owners who have Account Value allocated to the Subaccount that corresponds to this fund may leave their Account Value in this Subaccount, but future allocations and transfers into it are prohibited. If your most recent premium allocation instructions include the Subaccount that corresponds to this fund, premium received that would have been allocated to the Subaccount corresponding to this fund may be automatically allocated among the other available Subaccounts according to your most recent premium allocation instructions.  If your most recent allocation instructions do not include any available funds, you must provide us with alternative allocation instructions or the premium payment will be returned to you. You may give us alternative allocation instructions by contacting Customer Service at P.O. Box 5065, Minot, ND 58702-5065, 1-877-253-5050 or www.voyalifecustomerservice.com. See the Transfers section beginning on page 59 of your policy prospectus for information about making Subaccount transfers, including applicable restrictions and limits on transfers.

Your failure to provide us with alternative allocation instructions before we return your premium payment(s) may result in your policy entering the 61 day grace period and/or your policy lapsing without value. See the Lapse section on page 68 of your policy prospectus for more information about how to keep your policy from lapsing. See also the Reinstatement section beginning on page 68 of your policy prospectus for information about how to put your policy back in force if it has lapsed.

MORE INFORMATION IS AVAILABLE

More information about the funds available through your policy, including information about the risks associated with investing in them, can be found in the current prospectus and Statement of Additional Information for each fund. You may obtain these documents by contacting:

Customer Service

P.O. Box 5065

Minot, ND 58702-5065

1-877-253-5050

If you received a summary prospectus for any of the funds available through your policy, you may obtain a full prospectus and other fund information free of charge by either accessing the internet address, calling the telephone number or sending an email request to the email address shown on the front of the fund’s summary prospectus.

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