Analyst Duane Pfennigwerth also increased his price target for the Chicago-based company to $125, up from $105.
A year ago, shares were trading at $84.18.
In a note to investors, Pfennigwerth said United trades at a "significant valuation" discount in comparison with its peers combined with a longer-term co-brand credit card economics improvement potential and an Evercore ISI view of improved global GDP growth in 2020.
Pfenningwerth said that United provides choices for higher long-term earnings growth potential for free, given the significant relative discount, and an improved credit card deal is no longer baked into expectations.
In October, the air carrier reported third-quarter earnings ahead of analysts' expectations and raised its full-year guidance.
United Air reported GAAP earnings of $3.99 a share against $3.05 in the year-earlier quarter. Shares outstanding fell 6.3% to 256.4 million.
The airline reported adjusted earnings of $4.07 a share against the FactSet-derived analyst estimate of $3.95.
Revenue came in at $11.38 billion against the estimate of $11.42 billion.
United raised its full-year 2019 adjusted EPS guidance to a range of $11.25 to $12.25 a share from its previous view of $10.50 to $12. Wall Street expects the company to report earnings of $11.85 a share for this year.
The company said its overcame cost pressures in the quarter. United also said it purchased $363 million of common shares in the quarter at an average price of $88.22 each.