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EXHIBIT 12.1

BOSTON PROPERTIES LIMITED PARTNERSHIP
CALCULATION OF RATIO OF EARNINGS TO FIXED CHARGES

        Boston Properties Limited Partnership's ratios of earnings to fixed charges for the five years ended December 31, 2002 and the three months ended March 31, 2003 were as follows:

							Year Ended December 31,
				Three Months Ended March 31, 2003
							2002			2001			2000			1999			1998
							(dollars in thousands)
Earnings:
	Add:
		Income before minority interests in property partnerships, income from unconsolidated joint ventures, gains (losses) on sales of real estate and land held for development, discontinued operations, extraordinary items, cumulative effect of a change in accounting principle and preferred distributions		$	72,333		$	278,722		$	246,544		$	211,365		$	169,227		$	128,672
		Gains (losses) on sales of real estate and land held for development			64,694			233,304			11,238			(313	)		8,735			—
		Amortization of interest capitalized			659			2,526			950			415			153			22
		Distributions from unconsolidated joint ventures			3,083			8,692			2,735			1,848			972			—
		Fixed charges (see below)			84,458			316,835			306,709			275,607			242,199			124,164
	Subtract:
		Interest capitalized			(4,453	)		(22,510	)		(59,292	)		(37,713	)		(16,953	)		(6,933	)
		Preferred distributions			(6,360	)		(31,258	)		(36,026	)		(32,994	)		(32,111	)		(5,830	)
Total earnings				$	214,414		$	786,311		$	472,858		$	418,215		$	372,222		$	240,095
Fixed charges:
		Interest expensed		$	73,645		$	263,067		$	211,391		$	204,900		$	193,135		$	111,401
		Interest capitalized			4,453			22,510			59,292			37,713			16,953			6,933
		Preferred distributions			6,360			31,258			36,026			32,994			32,111			5,830
			Total fixed charges	$	84,458		$	316,835		$	306,709		$	275,607		$	242,199		$	124,164
Ratio of earnings to fixed charges					2.54			2.48			1.54			1.52			1.54			1.93

The ratio of earnings to fixed charges was computed by dividing earnings by fixed charges. Earnings consist of income before minority interests in property partnerships, income from unconsolidated joint ventures, discontinued operations, extraordinary items, cumulative effect of a change in accounting principle and preferred distributions, plus amortization of interest capitalized, distributions from unconsolidated joint ventures, fixed charges, minus interest capitalized and preferred distributions. Fixed charges consist of interest expensed, which includes credit enhancement fees and amortization of loan costs, interest capitalized, and preferred distributions.

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BOSTON PROPERTIES LIMITED PARTNERSHIP CALCULATION OF RATIO OF EARNINGS TO FIXED CHARGES