{"filing": {"accession": "0001999371-26-023426", "cik": "0001266585", "ticker": "NMZ", "company_name": "NUVEEN MUNICIPAL HIGH INCOME OPPORTUNITY FUND", "form_type": "424B5", "filing_type": "424B5", "filing_date": "2026-10-23", "accepted_datetime": null, "acceptance_datetime": null, "accepted_at": null, "primary_doc_url": "https://www.sec.gov/Archives/edgar/data/1266585/000199937126023426/0001999371-26-023426-index.htm", "filing_url": "https://www.sec.gov/Archives/edgar/data/1266585/000199937126023426/0001999371-26-023426-index.htm", "period_of_report": null}, "html_url": "/api/filings/000199937126023426/stream", "exhibits": [], "sections": [], "tables": [{"table_index": 1, "table_type": "financial", "caption": null, "header_text": "Per CommonShareTotal(1)"}, {"table_index": 2, "table_type": "financial", "caption": null, "header_text": "(1)Assumes that all Rights are exercised at the estimated Subscription Price (as described below). All of the Rights may not be\n exercised, and the estimated Subscription Price may be higher or lower "}, {"table_index": 6, "table_type": "financial", "caption": null, "header_text": ""}, {"table_index": 7, "table_type": "financial", "caption": null, "header_text": ""}, {"table_index": 8, "table_type": "financial", "caption": null, "header_text": "The\n FundNuveen Municipal High Income Opportunity Fund (the\n \u201cFund\u201d) is a diversified, closed-end management investment company. The Fund\u2019s common shares, $0.01\n par value per share (the \u201cCommon Share"}, {"table_index": 9, "table_type": "exhibit_index", "caption": null, "header_text": "Terms of the Rights OfferingOne Right will be issued for\n each Common Share held on the Record Date (as defined below). Rights are expected to trade on the NYSE under the symbol \u201cNMZ RT.\u201d The Rights w"}, {"table_index": 10, "table_type": "text", "caption": null, "header_text": "Subscription PriceThe subscription price per Common Share (the \u201cSubscription\n Price\u201d) will be determined based upon a formula equal to 95% of the average of the last reported sales price of the Common"}, {"table_index": 11, "table_type": "financial", "caption": null, "header_text": "Transfer of RightsThe Rights will be transferable. See \u201cDescription of\n the Rights Offering\u2014Terms of the Rights Offering,\u201d \u201cSale of Rights\u201d and \u201cMethod of Transferring\n Rights.\u201d"}, {"table_index": 12, "table_type": "financial", "caption": null, "header_text": "Common Shareholders are urged to obtain a recent trading price for the Rights on the NYSE from their broker, bank, financial\n advisor or the financial press."}, {"table_index": 14, "table_type": "text", "caption": null, "header_text": "EventDate"}, {"table_index": 17, "table_type": "text", "caption": null, "header_text": "Shareholder\u2019s\n Record Date PositionXOver-Subscription"}, {"table_index": 20, "table_type": "financial", "caption": null, "header_text": "Shareholder Transaction Expenses"}, {"table_index": 23, "table_type": "financial", "caption": null, "header_text": "Annual ExpensesAs\n a Percentageof Net AssetsAttributable toCommonShares(3)"}, {"table_index": 26, "table_type": "financial", "caption": null, "header_text": "(3)Stated as annualized\n percentages of average net assets attributable to Common Shares for the six-month period ended April 30, 2026\n (unaudited)."}, {"table_index": 28, "table_type": "text", "caption": null, "header_text": "1 Year3 Years5 Years10 Years"}, {"table_index": 30, "table_type": "text", "caption": null, "header_text": ""}, {"table_index": 31, "table_type": "financial", "caption": null, "header_text": "As ofOctober 16, 2026(unaudited)As Adjustedfor Offering(unaudited)"}, {"table_index": 34, "table_type": "text", "caption": null, "header_text": "Assumes\n the Primary Subscription is fully subscribed(1)"}, {"table_index": 35, "table_type": "text", "caption": null, "header_text": "(1)Actual amounts may vary due to rounding."}, {"table_index": 36, "table_type": "text", "caption": null, "header_text": "NAV(2)$9.28"}, {"table_index": 47, "table_type": "financial", "caption": null, "header_text": ""}, {"table_index": 71, "table_type": "text", "caption": null, "header_text": ""}, {"table_index": 72, "table_type": "financial", "caption": null, "header_text": "Average Daily Managed Assets*Fund-LevelFee Rate"}, {"table_index": 73, "table_type": "financial", "caption": null, "header_text": ""}], "exhibits_pending": false, "cdn_html": true, "response_time_ms": 43}