Notice to Shareowners of Pioneer Asset Allocation Trust In the combined annual report for Pioneer Solutions - Conservative Fund, Pioneer Solutions - Balanced Fund and Pioneer Solutions Growth Fund dated July 31, 2017, which was recently mailed to shareowners, the following shareholder meeting results were inadvertently omitted from the Notes to Financial Statements. Results of Shareholder Meeting At a special meeting held on June 13, 2017, shareholders of each Fund were asked to consider the proposals described below. A report of the total votes cast by each Fund's shareholders (or, with respect to Proposal 2, by shareholders of Pioneer Asset Allocation Trust, as noted below) follows: Pioneer Solutions - Conservative Fund: For Against Abstain Broker Non-Votes -------------------------------------------------------------------------------------- Proposal 1 - To 2,376,124.917 2,909.947 198,193.797 752,324.193 approve a New Management Agreement with Amundi Pioneer Asset Management, Inc. (the Adviser) -------------------------------------------------------------------------------------- Pioneer Solutions - Balanced Fund: For Against Abstain Broker Non-Votes -------------------------------------------------------------------------------------- Proposal 1 - To 6,331,283.651 64,933.760 240,474.111 1,991,999.300 approve a New Management Agreement with the Adviser -------------------------------------------------------------------------------------- Pioneer Solutions - Growth Fund: For Against Abstain Broker Non-Votes -------------------------------------------------------------------------------------- Proposal 1 - To 11,803,432.895 251,064.342 777,850.633 2,988,198.100 approve a New Management Agreement with the Adviser -------------------------------------------------------------------------------------- For Withhold -------------------------------------------------------------------------------------- Proposal 2 - To elect Trustees* -------------------------------------------------------------------------------------- David R. Bock 27,128,454.675 650,334.971 -------------------------------------------------------------------------------------- Benjamin M. Friedman 27,157,375.474 621,414.172 -------------------------------------------------------------------------------------- Margaret B.W. Graham 27,199,458.917 579,330.729 -------------------------------------------------------------------------------------- Lisa M. Jones 27,156,666.170 622,123.476 -------------------------------------------------------------------------------------- Lorraine H. Monchak 27,163,981.639 614,808.007 -------------------------------------------------------------------------------------- Thomas J. Perna 27,188,399.518 590,390.128 -------------------------------------------------------------------------------------- Marguerite A. Piret 27,145,820.636 632,969.010 -------------------------------------------------------------------------------------- Fred J. Ricciardi 27,181,298.954 597,490.692 -------------------------------------------------------------------------------------- Kenneth J. Taubes 27,212,288.440 566,501.206 -------------------------------------------------------------------------------------- * Proposal 2 was voted on and approved by all series of Pioneer Asset Allocation Trust. Results reported above reflect the combined votes of all series of the Trust. We apologize for this omission and any inconvenience that it may have caused. If you have any questions regarding this matter, please feel free to contact our Client Services Department at 1-800-225-6292 from Monday through Friday, 8 a.m. to 7 p.m. EST. Before investing, consider the Fund's investment objectives, risks, charges and expenses. Contact your advisor or Amundi Pioneer for a prospectus containing this information. Read it carefully. Securities offered through Amundi Pioneer Distributor, Inc. 60 State Street, Boston, MA 02109 Underwriter of Pioneer Mutual Funds, Member SIPC (c) 2017 Amundi Pioneer Asset Management 30594-00-1017 [LOGO] Amundi Pioneer ============== ASSET MANAGEMENT