NASDAQ:AMPH | Historical Stock Price | Amphastar Pharmaceuticals, Inc.

Complete retained daily price history on its own workbook tab. Split-adjusted close keeps every historical share price on one comparable split basis. Cumulative dividend-reinvested close is the daily close of a rebased total-return index: it starts with one share at the earliest retained close, reinvests every distribution, and normalizes every forward and reverse split exactly once. Admitted exchange opening prices remain a distinct current-session series.

Available history
2014-06-25 to 2026-09-04
Data captured

Stock Price Chart

Blue: Split-adjusted close · Orange: Cumulative dividend-reinvested close

$8.31$12.59$19.07$28.88$43.73$66.232014-06-252026-08-27

Logarithmic scale. Both lines share the same starting value for the selected range.

View year

Historical Stock Price — 2026

DateSplit-adjusted closeCumulative dividend-reinvested closeReported volumeOpen priceExchange Volume
2026-09-04$23.6139,049
2026-09-03$24.1524,321
2026-09-02$23.1431,611
2026-09-01$22.6215,965
2026-08-31$21.8014,460
2026-08-28$21.8411,193
2026-08-27$21.88$21.88259,800$21.6316,180
2026-08-26$22.02$22.02395,600$21.9529,382
2026-08-25$21.98$21.98283,800$21.4117,197
2026-08-24$21.52$21.52210,300$21.558,802
2026-08-21$21.60$21.60376,600$21.7316,506
2026-08-20$21.68$21.68338,700$21.3320,039
2026-08-19$21.74$21.74410,800$21.5328,550
2026-08-18$21.34$21.34411,800$21.0828,227
2026-08-17$20.86$20.86533,500$20.7832,069
2026-08-14$20.91$20.91305,700$20.0620,811
2026-08-13$20.18$20.18526,100$20.2128,205
2026-08-12$19.98$19.98343,800$20.2031,540
2026-08-11$20.42$20.42570,500$20.0327,518
2026-08-10$20.31$20.31645,700$20.5244,641
2026-08-07$20.78$20.781,301,000$22.46112,359
2026-08-06$19.81$19.81527,300$20.1332,581
2026-08-05$20.24$20.24351,600$20.1425,109
2026-08-04$19.90$19.90481,600$20.0728,784
2026-08-03$20.22$20.22413,200$20.3432,635
2026-07-31$19.94$19.94367,600$20.2022,684
2026-07-30$20.38$20.38355,700$20.2320,830
2026-07-29$20.58$20.58321,700$20.2322,167
2026-07-28$20.15$20.15390,800$19.5328,200
2026-07-27$19.18$19.18285,900$19.1318,095
2026-07-24$18.72$18.72445,700$19.1128,714
2026-07-23$18.87$18.87650,400$19.0346,294
2026-07-22$19.30$19.30409,200$19.8016,107
2026-07-21$19.59$19.59621,100$19.6346,102
2026-07-20$19.63$19.63437,400$19.8026,580
2026-07-17$19.75$19.75338,500
2026-07-16$19.86$19.86416,900
2026-07-15$19.40$19.40356,100
2026-07-14$18.81$18.81334,700
2026-07-13$19.29$19.29384,500
2026-07-10$18.72$18.72311,100
2026-07-09$19.02$19.02446,600
2026-07-08$18.88$18.88438,700
2026-07-07$20.08$20.08450,000
2026-07-06$19.61$19.61313,800
2026-07-02$19.64$19.64315,800
2026-07-01$20.10$20.10422,100
2026-06-30$20.18$20.18400,200
2026-06-29$20.71$20.71727,100
2026-06-26$21.78$21.78624,000
2026-06-25$21.04$21.04481,300
2026-06-24$21.02$21.02701,200
2026-06-23$19.53$19.53660,900
2026-06-22$18.33$18.33767,400
2026-06-18$18.81$18.811,327,600
2026-06-17$19.41$19.411,008,500
2026-06-16$19.96$19.96724,200
2026-06-15$19.71$19.71528,500
2026-06-12$20.09$20.09377,800
2026-06-11$20.53$20.53463,500
2026-06-10$20.29$20.29405,200
2026-06-09$20.16$20.16506,300
2026-06-08$19.39$19.39559,000
2026-06-05$19.74$19.74750,300
2026-06-04$18.70$18.70459,200
2026-06-03$18.12$18.12509,300
2026-06-02$18.45$18.45810,500
2026-06-01$18.42$18.42569,700
2026-05-29$18.85$18.85849,100
2026-05-28$19.30$19.30621,200
2026-05-27$19.10$19.10497,100
2026-05-26$18.81$18.81670,800
2026-05-22$18.41$18.41485,200
2026-05-21$18.16$18.161,657,000
2026-05-20$18.08$18.08868,800
2026-05-19$17.82$17.82725,100
2026-05-18$17.20$17.20866,000
2026-05-15$16.87$16.87679,300
2026-05-14$17.30$17.30739,100
2026-05-13$18.32$18.32971,200
2026-05-12$17.50$17.501,219,600
2026-05-11$18.45$18.451,359,600
2026-05-08$19.00$19.001,983,800
2026-05-07$24.03$24.03373,500
2026-05-06$23.90$23.90392,800
2026-05-05$23.39$23.39366,900
2026-05-04$22.74$22.74487,100
2026-05-01$21.88$21.88353,200
2026-04-30$21.96$21.96407,200
2026-04-29$21.63$21.63268,700
2026-04-28$21.82$21.82281,200
2026-04-27$21.65$21.65329,600
2026-04-24$21.41$21.41429,700
2026-04-23$21.01$21.01302,600
2026-04-22$20.99$20.99410,800
2026-04-21$21.21$21.21684,200
2026-04-20$22.92$22.92542,000
2026-04-17$22.88$22.88537,800
2026-04-16$21.81$21.81361,300
2026-04-15$21.68$21.68389,400
2026-04-14$21.38$21.38343,500
2026-04-13$21.36$21.36577,900
2026-04-10$20.37$20.37354,500
2026-04-09$20.87$20.87519,300
2026-04-08$20.40$20.40613,500
2026-04-07$20.58$20.58351,500
2026-04-06$20.58$20.58344,100
2026-04-02$20.45$20.45390,500
2026-04-01$20.24$20.24677,400
2026-03-31$19.59$19.59534,100
2026-03-30$19.22$19.22410,700
2026-03-27$19.01$19.01346,000
2026-03-26$19.53$19.53363,500
2026-03-25$19.57$19.57317,600
2026-03-24$19.23$19.23367,800
2026-03-23$19.23$19.23414,900
2026-03-20$19.50$19.501,133,200
2026-03-19$19.54$19.54583,100
2026-03-18$19.00$19.00650,400
2026-03-17$19.51$19.51635,600
2026-03-16$19.41$19.41738,000
2026-03-13$18.18$18.18604,600
2026-03-12$18.18$18.18901,700
2026-03-11$18.77$18.77548,300
2026-03-10$18.91$18.91527,100
2026-03-09$19.21$19.21687,800
2026-03-06$19.34$19.34753,600
2026-03-05$20.44$20.44726,300
2026-03-04$19.96$19.96595,000
2026-03-03$19.83$19.83740,800
2026-03-02$21.01$21.011,261,300
2026-02-27$20.23$20.231,965,500
2026-02-26$26.49$26.49816,500
2026-02-25$27.97$27.97416,000
2026-02-24$27.67$27.67478,100
2026-02-23$27.55$27.55496,700
2026-02-20$28.53$28.53508,400
2026-02-19$28.54$28.54340,700
2026-02-18$28.66$28.66325,900
2026-02-17$28.45$28.45316,900
2026-02-13$28.50$28.50268,700
2026-02-12$27.55$27.55437,500
2026-02-11$28.59$28.59236,600
2026-02-10$28.57$28.57182,600
2026-02-09$28.61$28.61285,000
2026-02-06$29.26$29.26343,800
2026-02-05$28.63$28.63287,600
2026-02-04$28.61$28.61378,900
2026-02-03$28.24$28.24506,300
2026-02-02$27.92$27.92444,100
2026-01-30$26.49$26.49294,500
2026-01-29$26.15$26.15184,400
2026-01-28$26.12$26.12209,000
2026-01-27$26.25$26.25264,500
2026-01-26$26.60$26.60316,200
2026-01-23$25.92$25.92269,500
2026-01-22$26.15$26.15233,300
2026-01-21$26.22$26.22251,600
2026-01-20$25.95$25.95282,600
2026-01-16$26.07$26.07286,900
2026-01-15$26.00$26.00584,100
2026-01-14$27.76$27.76472,400
2026-01-13$28.91$28.91345,600
2026-01-12$29.40$29.40455,700
2026-01-09$27.74$27.74247,200
2026-01-08$27.74$27.74304,400
2026-01-07$27.33$27.33342,800
2026-01-06$27.62$27.62300,100
2026-01-05$26.72$26.72419,200
2026-01-02$26.46$26.46406,000