Eupithecia swettii is a moth in the Geometridae family. It is found in eastern North America, from Quebec and Massachusetts to North Carolina in the south-east and through Missouri and Kansas to Mississippi. It is also found in eastern Texas. The length of the forewings is 8.5-10.5 mm. The forewings are light fawn brown shading to greyish brown. The hindwings are slightly paler than the forewings. Adults are on wing from January to April in the south and to May and even July in the north.