---
schema_version: "secwatch.filing_event.v1"
accession: "0000950170-24-037157"
form_type: "8-K"
ticker: "FISI"
cik: "0000862831"
company_name: "FINANCIAL INSTITUTIONS INC"
filed_at: "2024-03-27T23:59:59+00:00"
generated_at: "2026-06-04T07:30:53.484937+00:00"
event_type: "leadership"
sentiment: "neutral"
materiality_score: 0.25
calibrated_materiality_score: 0.25
confidence: "high"
source: SEC EDGAR
---

# Financial Institutions appoints Sandra Byers as Principal Accounting Officer

## Summary
- Sandra L. Byers, age 56, appointed SVP Controller and PAO upon retirement of Sonia Dumbleton.
- Byers served as Deputy Controller since October 2023; joined company as Assistant Controller in May 2021.
- Prior experience includes consulting, 12 years in banking (First Niagara, HSBC, M&T), and finance at Hardinge Inc.
- No family relationships with directors or execs; no material interest in reportable transactions.
- No additional compensation or equity grant tied to appointment; succession planned and previously announced.

## SEC filing metadata
- accession: 0000950170-24-037157
- form_type: 8-K
- ticker: FISI
- cik: 0000862831
- company_name: FINANCIAL INSTITUTIONS INC
- filed_at: 2024-03-27T23:59:59+00:00
- event_type: leadership
- sentiment: neutral
- materiality_score: 0.25
- calibrated_materiality_score: 0.25
- confidence: high
- sec_items: 5.02
- EDGAR index: https://www.sec.gov/Archives/edgar/data/862831/000095017024037157/0000950170-24-037157-index.htm
- EDGAR primary document: https://www.sec.gov/Archives/edgar/data/862831/000095017024037157/fisi-20240327.htm

## Machine-readable alternates
- HTML: https://secwatch.observer/filing/0000950170-24-037157
- JSON: https://secwatch.observer/filing/0000950170-24-037157.json
- Plain text: https://secwatch.observer/filing/0000950170-24-037157.txt

## Key facts
- Executive change
  Sonia M. Dumbleton retired as Controller at FINANCIAL INSTITUTIONS INC.
  - Action: retired
  - Role: Controller
  source text: Ms. Byers, age 56, was appointed Controller upon the previously announced retirement of Sonia M. Dumbleton, after serving as Deputy Controller since October 2, 2023.
  evidence_url: https://www.sec.gov/Archives/edgar/data/862831/000095017024037157/0000950170-24-037157-index.htm
- Executive change
  Sandra L. Byers was appointed as Principal Accounting Officer at FINANCIAL INSTITUTIONS INC.
  - Action: appointed
  - Role: Principal Accounting Officer
  source text: On March 27, 2024, Financial Institutions, Inc. (the “Company”) appointed Sandra L. Byers, Senior Vice President, Controller, as Principal Accounting Officer.
  evidence_url: https://www.sec.gov/Archives/edgar/data/862831/000095017024037157/0000950170-24-037157-index.htm

This AI-assisted summary is a reading aid. Review the linked SEC EDGAR filing before relying on any specific claim.