Nuveen S&P 500 Dynamic Overwrite Fund — Proxy Solicitation & Information Statement 2026

Jan 29, 2026

Filed by Nuveen S&P 500 Dynamic Overwrite Fund

(Commission File No. 333-290975)

pursuant to Rule 425 under the Securities Act of 1933, as amended,

and deemed filed pursuant to Rule 14a-6

under the Securities Exchange Act of 1934, as amended

Subject Company: Nuveen Dow 30 SM Dynamic Overwrite Fund

(Commission File No. 811-22970)

Nuveen Dow 30 SM Dynamic Overwrite Fund (DIAX)

Nuveen S&P 500 Buy-Write Income Fund (BXMX)

Please exercise your right to vote as soon as possible!

Dear Shareholder:

We recently sent you proxy materials concerning important proposals affecting your fund(s), which were considered at the Annual Meeting of Shareholders of the funds on January 29, 2026 at 2:00 p.m., Central Time. The Meeting has been adjourned to allow shareholders more time to vote. The Meeting will reconvene on March 5, 2026. This letter was sent because you held shares in the fund(s) on the record date and we have not received your vote .

YOUR FUND’S BOARD OF TRUSTEES RECOMMENDS THAT YOU VOTE "FOR" THE PROPOSALS

YOUR VOTE IS VERY IMPORTANT

VOTING NOW HELPS MINIMIZE PROXY COSTS, AVOIDS UNNECESSARY COMMUNICATIONS AND ELIMINATES PHONE CALLS TO SHAREHOLDERS

Your vote is very important. We encourage you as a shareholder to participate in your fund’s governance by returning your vote as soon as possible. If enough shareholders fail to cast their votes, a fund may not be able to hold its Meeting or the vote on the proposals and will be required to incur additional solicitation costs in order to obtain sufficient shareholder participation. Because your vote is critical, our outreach to you will continue until there is sufficient voting.

Please vote using one of the following options:

| ● | VOTE WITH A LIVE AGENT Call 1-866-585-5579 with any questions. Specialists can assist with voting. Available Monday-Friday from 9 a.m. – 11 p.m. and Saturday 12 p.m. –
6 p.m. ET |
| --- | --- |
| ● | VOTE ONLINE Log
on to the website or scan the QR code shown on your proxy card. Please have your proxy card in hand to access your control number (located
in the shaded box) and follow the on-screen instructions. |
| ● | VOTE BY TOUCH-TONE TELEPHONE Call the toll-free number listed on your
proxy card. Please have your proxy card in hand to access your control number (located in the shaded box) and follow the recorded instructions. |
| ● | VOTE BY MAIL Complete, sign and date the proxy card
and then return it in the enclosed postage paid envelope. |

The proxy materials we sent you contain important information regarding the proposals that you and other shareholders are being asked to consider. Please read the materials carefully.

View or download the proxy materials:

https://www.nuveen.com/en-us/investments/proxy-information#closed-end-funds

Thank you for your prompt attention to this matter. If you have already voted, we appreciate your participation.

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