Exhibit 11

POTASH CORPORATION OF SASKATCHEWAN INC.
COMPUTATION OF PER SHARE EARNINGS
FOR THE SIX MONTHS ENDED JUNE 30

	2009			2008
A   Net income as reported, Canadian GAAP ($ millions)		495.4			1,471.1
B   Items adjusting net income ($ millions)		(1.1	)		(27.4	)
C   Net income, US GAAP ($ millions)		494.3			1,443.7
D   Weighted average number of shares outstanding		295,338,000			313,138,000
E   Net additional shares issuable for diluted earnings per share calculation (Canadian GAAP)		8,398,000			10,578,000
F   Net additional shares issuable for diluted earnings per share calculation (US GAAP)		8,398,000			10,572,000
CANADIAN GAAP
Basic earnings per share (A/D)		1.68			4.70
Diluted earnings per share (A/(D+E))		1.63			4.54
UNITED STATES GAAP
Basic earnings per share (C/D)		1.67			4.61
Diluted earnings per share (C/(D+F))		1.63			4.46