Heartgard Plus (for heartworms):
Buy 12 doses and get a $15.00 mail-in rebate
Buy 6 doses of Heartgard and 6 doses of Nexgard/Frontline, get a $25 mail-in rebate
Buy 12 doses of Heartgard and 6 doses of Nexgard/Frontline, get a $35 mail-in rebate
Buy 12 doses of Heartgard and 12 doses of Nexgard/Frontline, get a $75 mail-in rebate

Nexgard (for fleas):
Buy 6 doses you get $15 mail in rebate
Buy 12 doses, get $35 mail in rebate