# EDGAR Filing Document

**Accession Number:** 0000816153
**File Stem:** 0001999371-26-006727
**Filing Date:** 2026-3
**Character Count:** 5316
**Document Hash:** eb7e91c842eb0e139bea60d374ba098d
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001999371-26-006727.hdr.sgml**: 20260323

**ACCESSION NUMBER**: 0001999371-26-006727

**CONFORMED SUBMISSION TYPE**: 497

**PUBLIC DOCUMENT COUNT**: 2

**FILED AS OF DATE**: 20260323

**DATE AS OF CHANGE**: 20260323

**EFFECTIVENESS DATE**: 20260323

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** THORNBURG INVESTMENT TRUST
- **CENTRAL INDEX KEY:** 0000816153

**ORGANIZATION NAME:**
- **EIN:** 061158764
- **STATE OF INCORPORATION:** MA
- **FISCAL YEAR END:** 0930

**FILING VALUES:**
- **FORM TYPE:** 497
- **SEC ACT:** 1933 Act
- **SEC FILE NUMBER:** 033-14905
- **FILM NUMBER:** 26783354

**BUSINESS ADDRESS:**
- **STREET 1:** 2300 NORTH RIDGETOP ROAD
- **CITY:** SANTA FE
- **STATE:** NM
- **ZIP:** 87506-8361
- **BUSINESS PHONE:** 5059840200

**MAIL ADDRESS:**
- **STREET 1:** 2300 NORTH RIDGETOP ROAD
- **CITY:** SANTA FE
- **STATE:** NM
- **ZIP:** 87506-8361

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** THORNBURG INCOME TRUST
- **DATE OF NAME CHANGE:** 19920703

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** LIMITED TERM TRUST
- **DATE OF NAME CHANGE:** 19870816

## Series and Classes Contracts Data

### Thornburg American Opportunities Fund (Series ID: S000011846)

---

|  |  |  |
|:---|:---|:---|
| Class Name                                       | Ticker Symbol | Class ID   |
| Thornburg American Opportunities Fund - Class A  | TVAFX         | C000032361 |
| Thornburg American Opportunities Fund - Class C  | TVCFX         | C000032363 |
| Thornburg American Opportunities Fund - Class I  | TVIFX         | C000032364 |
| Thornburg American Opportunities Fund - Class R5 | TVRRX         | C000032366 |
| Thornburg American Opportunities Fund - Class R4 | TVIRX         | C000042669 |
| Thornburg American Opportunities Fund - Class R3 | TVRFX         | C000042670 |

---

### Thornburg Focus Growth Fund (Series ID: S000011850)

---

|  |  |  |
|:---|:---|:---|
| Class Name                             | Ticker Symbol | Class ID   |
| Thornburg Focus Growth Fund - Class A  | THCGX         | C000032375 |
| Thornburg Focus Growth Fund - Class C  | TCGCX         | C000032376 |
| Thornburg Focus Growth Fund - Class I  | THIGX         | C000032377 |
| Thornburg Focus Growth Fund - Class R5 | THGRX         | C000032379 |
| Thornburg Focus Growth Fund - Class R4 | TCGRX         | C000042673 |
| Thornburg Focus Growth Fund - Class R3 | THCRX         | C000042674 |

---

## Series and Classes Contracts Data

### Thornburg American Opportunities Fund (Series ID: S000011846)

| Class ID   | Class Name                                       | Ticker Symbol   |
|:---|:---|:---|
| C000032361 | Thornburg American Opportunities Fund - Class A  | TVAFX           |
| C000032363 | Thornburg American Opportunities Fund - Class C  | TVCFX           |
| C000032364 | Thornburg American Opportunities Fund - Class I  | TVIFX           |
| C000032366 | Thornburg American Opportunities Fund - Class R5 | TVRRX           |
| C000042669 | Thornburg American Opportunities Fund - Class R4 | TVIRX           |
| C000042670 | Thornburg American Opportunities Fund - Class R3 | TVRFX           |

### Thornburg Focus Growth Fund (Series ID: S000011850)

| Class ID   | Class Name                             | Ticker Symbol   |
|:---|:---|:---|
| C000032375 | Thornburg Focus Growth Fund - Class A  | THCGX           |
| C000032376 | Thornburg Focus Growth Fund - Class C  | TCGCX           |
| C000032377 | Thornburg Focus Growth Fund - Class I  | THIGX           |
| C000032379 | Thornburg Focus Growth Fund - Class R5 | THGRX           |
| C000042673 | Thornburg Focus Growth Fund - Class R4 | TCGRX           |
| C000042674 | Thornburg Focus Growth Fund - Class R3 | THCRX           |

![](thornburg.jpg)

**THORNBURG INVESTMENT TRUST**

**Supplement dated March 23, 2026**

**to each Summary Prospectus, Prospectus and Statement of Additional Information ("SAI"), each dated January 15, 2026, as supplemented, of Thornburg American Opportunities Fund (formerly, Thornburg Small/Mid Cap Core Fund) and Thornburg Focus Growth Fund (formerly, Thornburg Small/Mid Cap Growth Fund) (each, a "Fund" and, together, the "Funds"), each a series of Thornburg Investment Trust**

------

Effective immediately, the investment advisory fee rate for each Fund is reduced and will be calculated in accordance with the following breakpoint schedule:

---

| | |
|:---|:---|
| &nbsp;&nbsp;**Net Assets of Fund** | &nbsp;&nbsp;**Advisory Fee Rate** |
| &nbsp;&nbsp;0 to $500 million | &nbsp;&nbsp;0.795% |
| &nbsp;&nbsp;$500 million to $1 billion | &nbsp;&nbsp;0.745% |
| &nbsp;&nbsp;$1 billion to $1.5 billion | &nbsp;&nbsp;0.695% |
| &nbsp;&nbsp;$1.5 billion to $2 billion | &nbsp;&nbsp;0.645% |
| &nbsp;&nbsp;Over $2 billion | &nbsp;&nbsp;0.595% |

---

In connection with this change, the breakpoint schedule relating to investment advisory fees in the "Investment Advisory and Administrative Services Fees" section of each Prospectus of each Fund is deleted and replaced in its entirety with the above breakpoint schedule.

\*\*\*

Shareholders should retain this supplement for future reference. This supplement provides new information beyond that contained in each Fund's Summary Prospectus, Prospectus and SAI and should be read in conjunction therewith.