Single Stock Concentration Risk 2027 Calculator
Single stock concentration risk: tech employee with $2M portfolio + $1M company RSUs = 33% concentration. Above 10% = elevated. Above 25% = dangerous. Historical drawdowns of single stocks 30-60% common; bankruptcies do happen (Enron, WeWork). Target diversification: <10% any single name.
10% Rule of Thumb
Vanguard, Schwab, financial advisors converge on <10% single-name as healthy. Above raises portfolio volatility 30-50%.
Tech RSU Common Issue
FAANG employees often 30-50% concentration. Vest + sell-same-day eliminates ongoing concentration buildup.
Tax-Efficient Diversification
Sell RSUs same-day at vest = no additional capital gains (already taxed at vest). Hold 1-year for long-term cap gains preference.
Source and Disclaimer
Vanguard, Schwab research. Historical examples: Enron, WeWork, Lehman.
Source: Vanguard, Schwab research. Last updated: May 2026.