# EDGAR Filing Document

**Accession Number:** 0001968890
**File Stem:** 0001754960-26-000161
**Filing Date:** 2026-2
**Character Count:** 10340
**Document Hash:** 4f7d9510a699da4964bba9bbb5489e05
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001754960-26-000161.hdr.sgml**: 20260209

**ACCESSION NUMBER**: 0001754960-26-000161

**CONFORMED SUBMISSION TYPE**: 13F-HR

**PUBLIC DOCUMENT COUNT**: 2

**CONFORMED PERIOD OF REPORT**: 20251231

**FILED AS OF DATE**: 20260209

**DATE AS OF CHANGE**: 20260206

**EFFECTIVENESS DATE**: 20260209

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Flagstone Financial Management
- **CENTRAL INDEX KEY:** 0001968890

**ORGANIZATION NAME:**
- **EIN:** 814389161
- **STATE OF INCORPORATION:** NE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 13F-HR
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 028-23158
- **FILM NUMBER:** 26609378

**BUSINESS ADDRESS:**
- **STREET 1:** 5801 HIDCOTE DR. STE 100
- **CITY:** LINCOLN
- **STATE:** NE
- **ZIP:** 68516
- **BUSINESS PHONE:** 402-413-0440

**MAIL ADDRESS:**
- **STREET 1:** 5801 HIDCOTE DR. STE 100
- **CITY:** LINCOLN
- **STATE:** NE
- **ZIP:** 68516

### FORM 13F COVER PAGE

**Report for the Calendar Year or Quarter Ended:** 12-31-2025

**Check here if Amendment** [ ] **Amendment Number:** 

**This Amendment (Check only one.):** [ ] is a restatement.

[ ] adds new holdings entries.

**Institutional Investment Manager Filing this Report:**

**Name:** Flagstone Financial Management<br>**Address:** 5801 HIDCOTE DR. STE 100<br>LINCOLN, NE 68516

**Form 13F File Number:** 028-23158

The institutional investment manager filing this report and the person by whom it is signed hereby represent that the person signing the report is authorized to submit it, that all information contained herein is true, correct and complete, and that it is understood that all required items, statements, schedules, lists, and tables, are considered integral parts of this form.

**Person Signing this Report on Behalf of Reporting Manager:**

**Name:** Aryn Sands<br>**Title:** Agent<br>**Phone:** 844-844-3453

**Signature, Place, and Date of Signing:**

Aryn Sands  Reno, NV  02-06-2026<br>[Signature]  [City, State]  [Date]

**Report Type (Check only one.):**

[x] **13F HOLDINGS REPORT.** (Check here if all holdings of this reporting manager are reported in this report.)

[ ] **13F NOTICE.** (Check here if no holdings are reported in this report, and all holdings are reported by other reporting manager(s).)

[ ] **13F COMBINATION REPORT.** (Check here if a portion of the holdings for this reporting manager are reported in this report and a portion are reported by other reporting manager(s).)

### Form 13F Summary Page

**Report Summary:**

**Number of Other Included Managers:** 0

**Form 13F Information Table Entry Total:** 66

**Form 13F Information Table Value Total:** $389914968

      (round to nearest dollar)

**List of Other Included Managers:**

Provide a numbered list of the name(s) and Form 13F file number(s) of all institutional investment managers with respect to which this report is filed, other than the manager filing this report.

[If there are no entries in this list, state “NONE” and omit the column headings and list entries.]

**NONE**

### FORM 13F INFORMATION TABLE

---

|  |  |  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| NAME OF ISSUER | TITLE OF CLASS | CUSIP | FIGI | VALUE (x$1000) | SHRS OR PRN AMT | SH/PRN | PUT/CALL | INVESTMENT DISCRETION | OTHER MANAGER | VOTING AUTHORITY | VOTING AUTHORITY | VOTING AUTHORITY |
| NAME OF ISSUER | TITLE OF CLASS | CUSIP | FIGI | VALUE (x$1000) | SHRS OR PRN AMT | SH/PRN | PUT/CALL | INVESTMENT DISCRETION | OTHER MANAGER | SOLE | SHARED | NONE |
| EATON CORP PLC | SHS | G29183103 |  | 211490 | 664 | SH |  | SOLE |  | 0 | 0 | 664 |
| ALPHABET INC | CAP STK CL C | 02079K107 |  | 902675 | 2877 | SH |  | SOLE |  | 0 | 0 | 2877 |
| ALPHABET INC | CAP STK CL A | 02079K305 |  | 308870 | 987 | SH |  | SOLE |  | 0 | 0 | 987 |
| AMAZON COM INC | COM | 023135106 |  | 339074 | 1469 | SH |  | SOLE |  | 0 | 0 | 1469 |
| AMERICAN CENTY ETF TR | REAL ESTATE ETF | 025072356 |  | 1222635 | 28087 | SH |  | SOLE |  | 29 | 0 | 28058 |
| AMERICAN CENTY ETF TR | AVANTIS EMGMKT | 025072604 |  | 7294082 | 94704 | SH |  | SOLE |  | 32 | 0 | 94672 |
| AMERICAN CENTY ETF TR | INTL EQT ETF | 025072703 |  | 4355011 | 52904 | SH |  | SOLE |  | 59 | 0 | 52845 |
| AMERICAN CENTY ETF TR | INTL SMCP VLU | 025072802 |  | 14492336 | 154223 | SH |  | SOLE |  | 0 | 0 | 154223 |
| AMERICAN CENTY ETF TR | US SML CP VALU | 025072877 |  | 19526044 | 191469 | SH |  | SOLE |  | 0 | 0 | 191469 |
| AMERICAN CENTY ETF TR | US EQT ETF | 025072885 |  | 14948071 | 133728 | SH |  | SOLE |  | 173 | 0 | 133555 |
| APPLE INC | COM | 037833100 |  | 3148906 | 11583 | SH |  | SOLE |  | 0 | 0 | 11583 |
| BANK AMERICA CORP | COM | 060505104 |  | 353958 | 6436 | SH |  | SOLE |  | 0 | 0 | 6436 |
| BERKSHIRE HATHAWAY INC DEL | CL A | 084670108 |  | 754800 | 1 | SH |  | SOLE |  | 0 | 0 | 1 |
| BERKSHIRE HATHAWAY INC DEL | CL B NEW | 084670702 |  | 6126808 | 12189 | SH |  | SOLE |  | 0 | 0 | 12189 |
| BOSTON OMAHA CORP | CL A COM STK | 101044105 |  | 299540 | 24215 | SH |  | SOLE |  | 0 | 0 | 24215 |
| DEERE  CO | COM | 244199105 |  | 480543 | 1032 | SH |  | SOLE |  | 0 | 0 | 1032 |
| DIMENSIONAL ETF TRUST | EMGR CRE EQT MNG | 25434V302 |  | 1031256 | 31663 | SH |  | SOLE |  | 0 | 0 | 31663 |
| DIMENSIONAL ETF TRUST | US EQUITY MARKET | 25434V401 |  | 110241286 | 1486333 | SH |  | SOLE |  | 0 | 0 | 1486333 |
| DIMENSIONAL ETF TRUST | US TARGETED VLU | 25434V609 |  | 244888 | 4113 | SH |  | SOLE |  | 0 | 0 | 4113 |
| DIMENSIONAL ETF TRUST | GLOBAL SUSTAINA | 25434V674 |  | 926535 | 17887 | SH |  | SOLE |  | 0 | 0 | 17887 |
| DIMENSIONAL ETF TRUST | EMERGING MARKETS | 25434V682 |  | 523090 | 12611 | SH |  | SOLE |  | 0 | 0 | 12611 |
| DIMENSIONAL ETF TRUST | INTERNATIONAL | 25434V690 |  | 820360 | 19147 | SH |  | SOLE |  | 0 | 0 | 19147 |
| DIMENSIONAL ETF TRUST | US SUSTAINABILTY | 25434V716 |  | 2253713 | 51893 | SH |  | SOLE |  | 0 | 0 | 51893 |
| DIMENSIONAL ETF TRUST | EMERGING MKTS CO | 25434V732 |  | 16301562 | 492792 | SH |  | SOLE |  | 0 | 0 | 492792 |
| DIMENSIONAL ETF TRUST | INTERNATNAL VAL | 25434V807 |  | 381784 | 7651 | SH |  | SOLE |  | 0 | 0 | 7651 |
| DIMENSIONAL ETF TRUST | US SMALL CAP VAL | 25434V815 |  | 1061198 | 32265 | SH |  | SOLE |  | 0 | 0 | 32265 |
| DIMENSIONAL ETF TRUST | US REAL ESTATE E | 25434V823 |  | 484715 | 21166 | SH |  | SOLE |  | 0 | 0 | 21166 |
| EQUITY LIFESTYLE PPTYS INC | COM | 29472R108 |  | 367600 | 6065 | SH |  | SOLE |  | 0 | 0 | 6065 |
| EXXON MOBIL CORP | COM | 30231G102 |  | 803912 | 6680 | SH |  | SOLE |  | 0 | 0 | 6680 |
| INVESCO QQQ TR | UNIT SER 1 | 46090E103 |  | 339099 | 552 | SH |  | SOLE |  | 0 | 0 | 552 |
| ISHARES TR | RUS MID CAP ETF | 464287499 |  | 753120 | 7823 | SH |  | SOLE |  | 0 | 0 | 7823 |
| ISHARES TR | RUSSELL 2000 ETF | 464287655 |  | 432750 | 1758 | SH |  | SOLE |  | 0 | 0 | 1758 |
| ISHARES TR | NATIONAL MUN ETF | 464288414 |  | 3196388 | 29842 | SH |  | SOLE |  | 0 | 0 | 29842 |
| ISHARES TR | ISHS 5-10YR INVT | 464288638 |  | 40961549 | 760236 | SH |  | SOLE |  | 0 | 0 | 760236 |
| ISHARES TR | 3 7 YR TREAS BD | 464288661 |  | 243713 | 2042 | SH |  | SOLE |  | 0 | 0 | 2042 |
| ISHARES TR | CORE MSCI EAFE | 46432F842 |  | 216314 | 2418 | SH |  | SOLE |  | 0 | 0 | 2418 |
| ISHARES TR | ESG AWRE 1 5 YR | 46435G243 |  | 2191892 | 86842 | SH |  | SOLE |  | 0 | 0 | 86842 |
| JPMORGAN CHASE  CO. | COM | 46625H100 |  | 1141143 | 3542 | SH |  | SOLE |  | 0 | 0 | 3542 |
| JOHNSON  JOHNSON | COM | 478160104 |  | 374777 | 1811 | SH |  | SOLE |  | 0 | 0 | 1811 |
| MARKEL GROUP INC | COM | 570535104 |  | 546012 | 254 | SH |  | SOLE |  | 0 | 0 | 254 |
| MASTERCARD INCORPORATED | CL A | 57636Q104 |  | 622259 | 1090 | SH |  | SOLE |  | 0 | 0 | 1090 |
| MICROSOFT CORP | COM | 594918104 |  | 2493062 | 5155 | SH |  | SOLE |  | 0 | 0 | 5155 |
| NVIDIA CORPORATION | COM | 67066G104 |  | 939472 | 5037 | SH |  | SOLE |  | 0 | 0 | 5037 |
| ORACLE CORP | COM | 68389X105 |  | 248900 | 1277 | SH |  | SOLE |  | 0 | 0 | 1277 |
| PEPSICO INC | COM | 713448108 |  | 287057 | 2000 | SH |  | SOLE |  | 0 | 0 | 2000 |
| PIMCO ETF TR | INTER MUN BD ACT | 72201R866 |  | 6064499 | 115713 | SH |  | SOLE |  | 0 | 0 | 115713 |
| ROCKWELL AUTOMATION INC | COM | 773903109 |  | 264957 | 681 | SH |  | SOLE |  | 0 | 0 | 681 |
| SPDR S 500 ETF TR | TR UNIT | 78462F103 |  | 230114 | 337 | SH |  | SOLE |  | 0 | 0 | 337 |
| SPDR INDEX SHS FDS | PORTFOLIO DEVLPD | 78463X889 |  | 29185876 | 657191 | SH |  | SOLE |  | 0 | 0 | 657191 |
| SPDR SERIES TRUST | STATE STREET SPD | 78464A375 |  | 389863 | 11531 | SH |  | SOLE |  | 0 | 0 | 11531 |
| SPDR SERIES TRUST | STATE STREET SPD | 78464A474 |  | 25735682 | 852175 | SH |  | SOLE |  | 0 | 0 | 852175 |
| SPDR SERIES TRUST | STATE STREET SPD | 78464A672 |  | 23711142 | 822162 | SH |  | SOLE |  | 0 | 0 | 822162 |
| SPDR SERIES TRUST | STATE STREET SPD | 78464A805 |  | 2064400 | 25023 | SH |  | SOLE |  | 0 | 0 | 25023 |
| SELECT SECTOR SPDR TR | STATE STREET FIN | 81369Y605 |  | 286278 | 5227 | SH |  | SOLE |  | 0 | 0 | 5227 |
| SELECT SECTOR SPDR TR | STATE STREET TEC | 81369Y803 |  | 219122 | 1522 | SH |  | SOLE |  | 0 | 0 | 1522 |
| SHOPIFY INC | CL A SUB VTG SHS | 82509L107 |  | 238236 | 1480 | SH |  | SOLE |  | 0 | 0 | 1480 |
| US BANCORP DEL | COM NEW | 902973304 |  | 1308718 | 24526 | SH |  | SOLE |  | 0 | 0 | 24526 |
| UNION PAC CORP | COM | 907818108 |  | 252945 | 1093 | SH |  | SOLE |  | 0 | 0 | 1093 |
| VANGUARD SPECIALIZED FUNDS | DIV APP ETF | 921908844 |  | 732038 | 3331 | SH |  | SOLE |  | 0 | 0 | 3331 |
| VANGUARD TAX-MANAGED FDS | VAN FTSE DEV MKT | 921943858 |  | 224642 | 3596 | SH |  | SOLE |  | 0 | 0 | 3596 |
| VANGUARD CHARLOTTE FDS | TOTAL INT BD ETF | 92203J407 |  | 21177385 | 438274 | SH |  | SOLE |  | 0 | 0 | 438274 |
| VANGUARD SCOTTSDALE FDS | INTER TERM TREAS | 92206C706 |  | 601038 | 10029 | SH |  | SOLE |  | 0 | 0 | 10029 |
| VANGUARD INDEX FDS | REAL ESTATE ETF | 922908553 |  | 9924110 | 112150 | SH |  | SOLE |  | 0 | 0 | 112150 |
| VANGUARD INDEX FDS | TOTAL STK MKT | 922908769 |  | 699875 | 2088 | SH |  | SOLE |  | 0 | 0 | 2088 |
| WALMART INC | COM | 931142103 |  | 305767 | 2745 | SH |  | SOLE |  | 0 | 0 | 2745 |
| WELLS FARGO CO NEW | COM | 949746101 |  | 1104032 | 11846 | SH |  | SOLE |  | 0 | 0 | 11846 |

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