By Bill Bell | On the Road in Mexico
Canadians driving to Mexico with a dog have been asking whether a short journey through the United States triggers Mexico’s screwworm inspection certificate requirement. I wrote directly to SENASICA, Mexico’s national animal-health authority, to ask about a specific case: a pet dog living in Canada, travelling with its owner for noncommercial purposes and spending approximately two days crossing the United States.
In its written reply, SENASICA says the GBG inspection certificate is not necessary for the two-day transit described in that inquiry. The response is specific to that scenario. It does not establish an exemption for every Canadian dog or every length of stay in the United States.
What SENASICA told us
- Two-day transit: the certificate is not necessary when the journey from Canada through the United States meets the two-day transit duration described.
- Longer journeys: SENASICA asks travellers whose transit is extended, including additional overnight stays, to submit their circumstances to the department for assessment.
- If the certificate is required: the email says it must be issued by a veterinarian accredited by the U.S. government and is valid for five days after issuance.
- Evidence of Canadian origin: a vaccination record identifying Canada and recording vaccination and deworming treatments can help establish origin.
- Border crossings: SENASICA says the same requirements apply at all entry points.
Check your own itinerary before travelling
The reply does not define the two-day period in hours or set out a separate rule for each U.S. state. If your trip takes longer or differs from the case described, ask SENASICA to assess it rather than assuming this answer covers your circumstances.
SENASICA directs travellers to its official animal-health requirements consultation module and recommends checking the requirements for dogs before departure because they can change with animal-health conditions.
My thanks to SENASICA for providing a written response. Below are the four questions and answers, translated from the Spanish email supplied to us.
The questions and SENASICA’s answers
English translation. GBG refers to “gusano barrenador del ganado,” or New World screwworm. Answers are attributed to SENASICA’s email; this article is not a substitute for the current requirements sheet.
1. Is a screwworm inspection certificate required because the dog passes through the United States, even though the journey starts in Canada?
Presentation of the GBG Inspection Certificate for the Movement of Pet Dogs from the United States to Mexico will not be necessary, provided that the journey from Canada to Mexico through the United States meets the two-day transit duration.
2. Do the duration, overnight stays or U.S. states travelled through matter? Is there a documented exception for brief transit?
Yes. The duration of transit and subsequent overnight stays must be assessed by this department. Therefore, those whose journeys and transit periods are extended should submit an inquiry by this means regarding presentation of the GBG Inspection Certificate.
3. If a certificate is required, who issues it, how long is it valid, and can it be issued in Canada?
The GBG Inspection Certificate for the Movement of Pet Dogs from the United States to Mexico is issued only by veterinarians accredited by the U.S. government and is valid for only five days after it is obtained. In that respect, a certificate issued by another authority is not accepted. This requirement took effect on August 3, 2026.
4. What establishes Canadian origin, and do the same requirements apply at all crossings, including Nogales and Baja California?
Since December 2019, dogs entering Mexico from Canada have not needed a health certificate or proof of vaccination to enter Mexico. However, a vaccination record specifying the country and deworming/vaccination treatments can establish Canadian origin.
The same requirements apply at all points of entry into Mexico.
Response from: MVZ Aisha Itzel Gómez Cruz, Responsable 3, SENASICA.
Source: SENASICA’s written email response to Bill Bell. The email also referred to an attached Animal Health Requirements Sheet (HRZ). That attachment was not available for review when this article was prepared and is not reproduced here. This clarification concerns entry into Mexico, not U.S. entry or the return journey to Canada.
