Retirement Plans (Tables)

9 Months Ended

Oct. 03, 2021

Defined Benefit Pension Plans

Net Periodic Pension and Postretirement Benefit Costs

For the three and nine months ended October 3, 2021 and September 27, 2020, Teradyne’s net periodic pension cost was comprised of the following components:

	For the Three Months Ended
	October 3, 2021						September 27, 2020
	United   States			Foreign			United   States			Foreign
	(in thousands)
Service cost	$	452		$	240		$	417		$	216
Interest cost		1,098			86			1,460			123
Expected return on plan assets		(936	)		(17	)		(1,170	)		(16	)
Net actuarial loss		—			—			2,238			—
Settlement loss		—			—			450			—
Total net periodic pension cost	$	614		$	309		$	3,395		$	323
	For the Nine Months Ended
	October 3, 2021						September 27, 2020
	United   States			Foreign			United   States			Foreign
	(in thousands)
Service cost	$	1,357		$	720		$	1,283		$	648
Interest cost		3,295			257			4,505			369
Expected return on plan assets		(2,809	)		(50	)		(3,634	)		(47	)
Net actuarial (gain) loss		(400	)		—			2,418			—
Settlement loss		—			—			450			—
Total net periodic pension cost	$	1,443		$	927		$	5,022		$	970

Postretirement Benefit Plans

Net Periodic Pension and Postretirement Benefit Costs

For the three and nine months ended October 3, 2021 and September 27, 2020, Teradyne’s net periodic postretirement benefit cost (credit) was comprised of the following components:

	For the Three Months Ended						For the Nine Months Ended
	October 3,   2021			September 27,   2020			October 3,   2021			September 27,   2020
	(in thousands)
Service cost	$	16		$	14		$	48		$	43
Interest cost		43			60			128			180
Amortization of prior service credit		(2	)		(2	)		(7	)		(7	)
Net actuarial gain		—			—			(228	)		(279	)
Total net periodic postretirement benefit cost (credit)	$	57		$	72		$	(59	)	$	(63	)