Adjusting the mechanical properties of polyester-based vascular grafts is crucial to achieving long-term success in vivo. Although previous studies using a fabric-based approach have achieved some success, a central issue with pure poly(lactic acid) (PLA) or poly(glycolic acid) (PGA) grafts sealed with poly(dl-caprolactone-co-lactic acid) (P(CL/LA)) has been stenosis. Intimal hyperplasia, a leading cause of stenosis, can be caused by the mechanical incompatibility of synthetic vascular grafts. Investigating the performance of poly(glycolic-co-lactic acid) (PGLA) grafts could lead to insight into whether graft stenosis stems from mechanical issues such as noncompliance and unfavorable degradation times. This could be achieved by examining grafts with tunable mechanical properties between the ranges of such properties in pure PGA and PLA-based grafts. In this study, we examined PGLA-based grafts sealed with different P(CL/LA) solutions to determine the PGLA-P(CL/LA) grafts' mechanical properties and tissue functionality. Cell attachment and proliferation on graft surfaces were also observed. For in vivo assessment, grafts were implanted in a mouse model. Mechanical properties and degradation times appeared adequate compared to recorded values of vessels used in autograft procedures. Initial neotissue formation was observed in the grafts and patency maintained during the pilot study. This study presents a ∼1-mm diameter degradable graft demonstrating suitable mechanical properties and in vivo pilot study success, enabling further investigation into the tuning of mechanical properties to reduce complications in degradable polyester fabric-based vascular grafts. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 1972–1981, 2014.