American Express Company (AXP) vs Quest Diagnostics Incorporated (DGX): Which Is the Better Buy in 2026?
As of 2026-08-03, AXP is undervalued at $336, with a DCF intrinsic value of $477 and a margin of safety of 30%. DGX is overvalued at $233, with an intrinsic value of $149 and a margin of safety of -56%. Of the two, AXP has the wider margin of safety.
Rewards
- ★Gross margin of 62.3% indicates strong pricing power — typical of businesses with significant intellectual property or brand strength.
- ★American Express Company scores 100/100 on the Economic Moat Score (Wide Moat), with revenue predictability as the strongest competitive dimension.
- ★Return on equity has consistently exceeded 20% over 4 years, indicating efficient use of shareholder capital.
Risks
- ⚠Altman Z-Score of 0.93 places the company in the distress zone — financial patterns resemble those of companies that experienced bankruptcy.
- ⚠Insiders have sold $2.4M worth of stock in the past 3 months — significant insider liquidation.
- ⚠Free cash flow has declined at a 5.9% CAGR over the past 4 years — a concerning trend.
- ⚠Each dollar of retained earnings has produced only $0.36 of earning power — shareholders may have been better served by dividends.
- ⚠FCF yield of 5.3% suggests reasonable valuation assuming continued moderate growth.
- ⚠Trailing P/E of 24.8x is 30% above the historical average of 19.1x — the stock trades at a premium to its own history.
Key Valuation Metrics
Learn more →Historical Fundamentals
Learn more →Price ÷ Earnings Per Share — how many years of current earnings you're paying for at today's price. Lower P/E may indicate undervaluation. The dashed forward point is the forward P/E — today's price ÷ analyst consensus EPS.
Price ÷ Earnings Per Share — how many years of current earnings you're paying for at today's price. Lower P/E may indicate undervaluation. The dashed forward point is the forward P/E — today's price ÷ analyst consensus EPS.
Price ÷ Earnings Per Share — how many years of current earnings you're paying for at today's price. Lower P/E may indicate undervaluation. The dashed forward point is the forward P/E — today's price ÷ analyst consensus EPS.
$1 Retained Earnings Test
Learn more →> $1 created per $1 retained = Value Creator · < $1 created = Value Destroyer
> $1 created per $1 retained = Value Creator · < $1 created = Value Destroyer
Buffett's "$1 Test": For every $1 of earnings retained, has management created at least $1 of market value?
> $1 created per $1 retained = Value Creator · < $1 created = Value Destroyer
Discounted Cash Flow (DCF) Analysis
Learn more →Reverse DCF — Market-Implied Growth
Learn more →Requires positive FCF to compute implied growth rate.
What growth rate is the market pricing in at $233?
The market implies +13.4% Owner Earnings growth, above historical trends.
Standard FCF implies a demanding +9.7%, reflecting heavy growth investment.
Economic Moat Score
Learn more →Wide moat driven primarily by revenue predictability. Margin Stability is the area most vulnerable to competitive pressure.
Narrow moat with margin stability as the key competitive advantage. Improving roic consistency would strengthen the moat.
Forensic Accounting
Learn more →M-Score Trend
M-Score Trend
Beneish's 8-variable model estimates the probability of earnings manipulation. An M-Score above -1.78 signals elevated risk — companies in this range have historically been 3-5× more likely to be manipulating earnings. Scores between -2.22 and -1.78 fall in a grey zone warranting further investigation.
Ownership Breakdown
Learn more →High insider ownership aligns management incentives with shareholders. Institutional concentration can indicate smart-money conviction but also crowding risk.
Insider Buying Activity
Learn more →Open market purchases · includes direct & indirect ownership · excludes option exercises.
Insider Selling Activity
Learn more →Direct ownership only · excludes indirect, option exercises, planned (10b5-1) sales & derivatives.
🎭 Mr. Market's Mood
Learn more →"Market is pricing this stock without strong emotion in either direction"
"Market is optimistic — be cautious and ensure you have a margin of safety"
Composite sentiment score based on market signals. Inspired by Buffett’s "Mr. Market" allegory — fear = potential opportunity, greed = potential risk. Must be used alongside fundamental analysis, not in isolation.
⚖️ Buffett Signal
Learn more →The Buffett Signal cross-references market sentiment with DCF valuation. Configure the DCF Analysis above to generate a signal.
The Buffett Signal cross-references market sentiment with DCF valuation. Configure the DCF Analysis above to generate a signal.
Frequently Asked Questions: AXP vs DGX
Is American Express Company or Quest Diagnostics Incorporated more undervalued in 2026?▼
Based on our discounted cash flow model, AXP trades at a 29.5% margin of safety (intrinsic value $477 vs. price $336), compared to DGX's -56.3% margin of safety (intrinsic $149 vs. $233).
Which stock has a wider economic moat, American Express Company or Quest Diagnostics Incorporated?▼
AXP scores 100/100 (Wide moat), while DGX scores 56/100 (Narrow moat). The moat score measures competitive advantage durability across ROIC consistency, margin stability, revenue predictability, and reinvestment efficiency.
Is American Express Company in financial distress?▼
AXP's Altman Z-Score of 0.9 places it in the Distress zone, signaling elevated bankruptcy risk. DGX scores 3.1 (Safe zone). The Altman Z-Score is a five-factor model that predicts insolvency within two years; scores below 1.81 indicate significant distress.
Which stock has higher return on invested capital, American Express Company or Quest Diagnostics Incorporated?▼
AXP earns 12.2% ROIC versus DGX's 9.7%. A higher ROIC means the company generates more profit per dollar of capital employed, a hallmark of durable competitive advantage in Buffett-style analysis.
Which dividend is safer, American Express Company's or Quest Diagnostics Incorporated's?▼
DGX's dividend earns a safety score of 94/100 (Very Safe), compared to AXP's 94/100 (Very Safe). DGX has raised its dividend for 3 consecutive years.