For adopted dogs, adjusting to a new home isn’t something that happens overnight. While many behavior issues improve over time, challenges like aggression or destruction can lead to dogs being returned. Health concerns are a less common reason for return but still affect outcomes. At the same time, rehoming organizations often lack the resources to check in with guardians after adoption.

Previous research on the topic has faced a number of limitations. Most past studies have tracked fewer than 100 dogs post-adoption and ended after just a few weeks. Different methods and definitions make it hard to compare findings or apply them broadly. Thus, more reliable, long-term data is needed to better support both dogs and their guardians.

To help fill this gap, Dogs Trust, a large dog welfare organization in the U.K., launched the Post Adoption Support project in 2018. The goal of the project is to provide tailored support to new guardians and collect detailed, longitudinal data on the health and behavior of adopted dogs.

As part of the project, all adopters are offered follow-up phone calls at two days, two weeks, and four months post-adoption. During these calls, Dogs Trust staff ask standardized questions about the health and behavior of their newly adopted dog, as well as their experience and satisfaction with the adoption. Adopters are also given the chance to speak to a behavior advisor or veterinary nurse at no cost, if needed.

For this study, researchers focused on calls made to guardians of dogs rehomed from 20 Dogs Trust centers over a six-month period from June to December 2019.

Key Findings

The study included 5,567 adoptions. Most dogs were mixed breeds (62%) and more than half were male (57%). Adult dogs made up the largest group (40%), followed by adolescents (26%) and seniors (19%).

At six months post-adoption, 85% of dogs were still in their adoptive homes. Almost all guardians (99%) consented to the two-day follow-up call, while 84% took part in the two-week and four-month check-ins.

Health Problems After Adoption

Health concerns were common soon after adoption. At the two-day check-in, 56% of guardians reported at least one health issue. This number dropped to 17% at two weeks, but rose again to 39% at four months. Vomiting and diarrhea were the most commonly reported issues throughout the study period.

The authors suggest that the increase at four months may be due to delayed-onset conditions or more detailed prompting during the final call. This pattern highlights the need for ongoing monitoring, not just early intervention.

Behavior Problems After Adoption

More than half of adopters reported at least one behavior concern at each check-in. Potentially aggressive behaviors were noted by 36% of adopters at two days, 44% at two weeks, and 42% at four months. Most of the reported behaviors were non-contact, such as growling, lunging, or staring. Contact behaviors like biting, grabbing, or mouthing directed at people or other animals were less common.

Separation-related stress was another common challenge. Among dogs who were left alone, 37% showed signs of distress at two days, falling to 15% by four months.

Other frequently reported concerns included pulling on the leash, barking or whining, guarding food or toys, and toileting issues.

Support And Satisfaction

At the two-day check-in, 60% of guardians were offered a callback for support. Most were for behavior concerns (72.5%), while 11% were for health concerns and 16% were for a combination of health and behavior concerns. Even with these challenges, satisfaction with adoption was very high: at least 98% of guardians said they were happy with the adoption at all timepoints, while fewer than 1% said they were unhappy.

The study also found a 15% re-relinquishment rate, which the authors say is consistent with earlier research but now based on a much larger sample. This figure helps ground expectations and highlights the importance of support during the early adjustment period.

Study Limitations

The authors note some key drawbacks to the project’s design and findings. They couldn’t track how severe or frequent each issue was, and the data came from guardian reports, not veterinary or behavioral diagnoses. Further, the results may be affected by who chose to take part in the study, as it doesn’t include feedback from people who didn’t respond or who returned their dog early. Finally, no demographic data was collected, which limits understanding of how well the sample reflects the wider U.K. dog guardian population.

What Advocates Can Do With This

This study gives a detailed look at what newly adopted dogs and their guardians experience in the first few months. The findings reveal a clear message: many guardians encounter health and behavior issues that would benefit from post-adoption support. This support can include:

• Providing new guardians with honest expectations. Common issues like upset stomachs or mild behavior quirks often pass.
• Offering a few quick check-ins in the days, weeks, and months following adoption.
• Providing access to behavior advice or helplines. Most support requests were related to behavior.

While more research is needed, it’s hoped that by making post-adoption support part of standard practice, rehoming organizations can reduce returns and improve outcomes for both dogs and their new families. Advocates can use this data to push for more funding, staffing, and training focused on post-adoption care — not just getting dogs into homes but helping them stay there.