Amazon has select PurolatorONE and PurolatorBOSS oil filters for as low as $2.75 FS w/ Prime with clipped coupon. Some are Prime items and some are add-ons.
Example: Purolator PL14612 PurolatorONE Oil Filter, $2.75 shipped W/ Prime after $3.00 clipped coupon.
https://www.amazon.com/gp/product…0DER&
Full list of PurolatorONE oil filters with $3 eligible coupon savings:
https://www.amazon.com/gp/coupon/…LTFPVJ5JRR
Full list of PurolatorBOSS oil filters with $4 eligibile coupon savings:
https://www.amazon.com/gp/coupon/…5D9P7IZRWF