This is a good resource from Colorado State but realize the months may change based on your location and environmental conditions as well as what is prevalent in your area or has developed resistance. http://csu-cvmbs.colostate.edu/Docum...g-schedule.pdf
You can also type in "printable horse deworming chart" and find one for your area.
This is an example of a blanket paste dewormer schedule for the northeast U.S. Paste Deworming Protocol:
This schedule is recommended for the Northeastern United States for horses not on a continuous deworming program.( i.e. daily Strongid C 2X):
January-Ivermectin/praziquantel combination (Equimax)
May-Moxidectin (Quest) ( Use in horses only. We do not recommend using in miniature horses or ponies.)
May-Ivermectin (Equell) for miniature horses and ponies
July-Double dose Pyrantel Pamoate (Strongid)
September-Ivermectin/Praziquantel combination (Equimax)
November-Double dose Fenbendazole (Panacur) This can be repeated for 4 more days if horse is showing signs of small strongyle infestation (poor coat, chronic colic, diarrhea, unthrifty)
**Remember to read the active ingredient. For example fenbendazole is the active ingredient in Panacur and Safeguard.
This link shows what is recommended where I live as I am considered southeast. It goes more into resistance and temperatures necessary for egg hatch and when worming is not needed based on that. https://vetmed.tennessee.edu/vmc/Equ...%20Control.pdf