Prospectus by Investment Company (Form 497)

SMA Relationship Trust

Prospectus Supplement | September 25, 2026

Includes:

Dear Investor,

The purpose of this supplement is to update the information in the Prospectus, dated April 30, 2026, for Series M (the "Fund"), a series of SMA Relationship TrustSM (the "Trust"), as follows:

Effective October 1, 2026, the Fund's style benchmark will change from the Bloomberg Managed Money Intermediate (1-17) Index to a 50/50 blend of the Bloomberg Managed Money Intermediate (1-17) Index and the Bloomberg Managed Money Short/Intermediate (1-10) Index.

The information contained in the first paragraph under the heading "Series M-Fund Summary" and the sub-heading "Performance-Risk/return bar chart and table" is deleted in its entirety and replaced with the following:

The performance information that follows shows the Fund's performance information in a bar chart and an average annual total returns table. The information provides some indication of the risks of investing in the Fund by showing changes in the Fund's performance year to year and by showing how the Fund's average annual total returns (before and after taxes) compare with the returns of a broad measure of market performance. The Fund's performance information does not reflect the maximum annual wrap program or other similar fee; if it did, the total returns shown would be lower. An additional index, a 50/50 blend of the Bloomberg Managed Money Intermediate (1-17) Index and the Bloomberg Managed Money Short/Intermediate (1-10) Index, shows how the Fund's performance compares to a blended index with characteristics relevant to the Fund. The Bloomberg Managed Money Intermediate (1-17) Index and the Bloomberg Managed Money Short/Intermediate (1-10) Index are unmanaged sub-indexes of the Bloomberg Municipal Managed Money Index, which is a rules-based, market-value-weighted index designed to track the performance of municipal securities issued by state and local municipalities whose interest is exempt from federal income tax and the federal alternative minimum tax. Indices reflect no deduction for fees, expenses or taxes. The Fund's past performance (before and after taxes) is not necessarily an indication of how the Fund will perform in the future.

ZS-1306

The table under the heading "Series M-Fund Summary" and the sub-heading "Performance-Average annual total returns" is deleted in its entirety and replaced with the following:

Average annual total returns (for the periods ended December 31, 2025)

PLEASE BE SURE TO RETAIN THIS IMPORTANT INFORMATION FOR FUTURE REFERENCE.

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