diff --git a/carton/buildpack_dependency.go b/carton/buildpack_dependency.go
index b2ef05b..428a6b8 100644
--- a/carton/buildpack_dependency.go
+++ b/carton/buildpack_dependency.go
@@ -35,6 +35,7 @@ const (
 type BuildpackDependency struct {
 	BuildpackPath  string
 	ID             string
+	Arch           string
 	SHA256         string
 	URI            string
 	Version        string
@@ -58,6 +59,7 @@ func (b BuildpackDependency) Update(options ...Option) {
 
 	logger := bard.NewLogger(os.Stdout)
 	_, _ = fmt.Fprintf(logger.TitleWriter(), "\n%s\n", bard.FormatIdentity(b.ID, b.VersionPattern))
+	logger.Headerf("Arch:         %s", b.Arch)
 	logger.Headerf("Version:      %s", b.Version)
 	logger.Headerf("PURL:         %s", b.PURL)
 	logger.Headerf("CPEs:         %s", b.CPE)
@@ -141,7 +143,28 @@ func (b BuildpackDependency) Update(options ...Option) {
 			continue
 		}
 
-		if depId == b.ID {
+		// extract the arch from the PURL, it's the only place it lives consistently at the moment
+		var depArch string
+		purlUnwrapped, found := dep["purl"]
+		if found {
+			purl, ok := purlUnwrapped.(string)
+			if ok {
+				purlArchExp := regexp.MustCompile(`arch=(.*)`)
+				purlArchMatches := purlArchExp.FindStringSubmatch(purl)
+				if len(purlArchMatches) == 2 {
+					depArch = purlArchMatches[1]
+				}
+			}
+		}
+
+		// if not set, we presently need to default to amd64 because a lot of deps do not specify arch
+		//   in the future when we add the arch field to our deps, then we can remove this because empty should then mean noarch
+		if depArch == "" {
+			depArch = "amd64"
+		}
+
+		if depId == b.ID && depArch == b.Arch {
+
 			depVersionUnwrapped, found := dep["version"]
 			if !found {
 				continue
@@ -151,6 +174,7 @@ func (b BuildpackDependency) Update(options ...Option) {
 			if !ok {
 				continue
 			}
+
 			if versionExp.MatchString(depVersion) {
 				dep["version"] = b.Version
 				dep["uri"] = b.URI
diff --git a/carton/buildpack_dependency_test.go b/carton/buildpack_dependency_test.go
index 48f0842..a1e1a03 100644
--- a/carton/buildpack_dependency_test.go
+++ b/carton/buildpack_dependency_test.go
@@ -74,6 +74,7 @@ source-sha256 = "test-source-sha256-1"
 		d := carton.BuildpackDependency{
 			BuildpackPath:  path,
 			ID:             "test-id",
+			Arch:           "amd64",
 			SHA256:         "test-sha256-2",
 			URI:            "test-uri-2",
 			Version:        "test-version-2",
@@ -123,6 +124,7 @@ cpes    = ["cpe:2.3:a:test-vendor:test-product:test-version-1:patch1:*:*:*:*:*:*
 		d := carton.BuildpackDependency{
 			BuildpackPath:  path,
 			ID:             "test-id",
+			Arch:           "amd64",
 			SHA256:         "test-sha256-2",
 			URI:            "test-uri-2",
 			Version:        "test-version-2",
@@ -174,6 +176,7 @@ cpes    = ["cpe:2.3:a:test-vendor:test-product:test-version-1:patch1:*:*:*:*:*:*
 		d := carton.BuildpackDependency{
 			BuildpackPath:  path,
 			ID:             "test-id",
+			Arch:           "amd64",
 			SHA256:         "test-sha256-2",
 			URI:            "test-uri-2",
 			Version:        "test-version-2",
@@ -182,8 +185,8 @@ cpes    = ["cpe:2.3:a:test-vendor:test-product:test-version-1:patch1:*:*:*:*:*:*
 			PURLPattern:    `different-version-[\d]`,
 			CPE:            "test-version-2:patch2",
 			CPEPattern:     `test-version-[\d]:patch[\d]`,
-			Source:          "test-new-source",
-			SourceSHA256:    "test-new-source-sha",
+			Source:         "test-new-source",
+			SourceSHA256:   "test-new-source-sha",
 		}
 
 		d.Update(carton.WithExitHandler(exitHandler))
@@ -243,6 +246,7 @@ source-sha256 = "test-source-sha256-2"
 		d := carton.BuildpackDependency{
 			BuildpackPath:  path,
 			ID:             "test-id",
+			Arch:           "amd64",
 			SHA256:         "test-sha256-3",
 			URI:            "test-uri-3",
 			Version:        "test-version-3",
@@ -309,6 +313,7 @@ cpes    = ["cpe:2.3:a:test-vendor:test-product:test-version-1:patch1:*:*:*:*:*:*
 		d := carton.BuildpackDependency{
 			BuildpackPath:  path,
 			ID:             "test-id",
+			Arch:           "amd64",
 			SHA256:         "test-sha256-2",
 			URI:            "test-uri-2",
 			Version:        "test-version-2",
@@ -359,6 +364,7 @@ cpes    = ["cpe:2.3:a:test-vendor:test-product:test-version-1:patch1:*:*:*:*:*:*
 		d := carton.BuildpackDependency{
 			BuildpackPath:  path,
 			ID:             "test-id",
+			Arch:           "amd64",
 			SHA256:         "test-sha256-2",
 			URI:            "test-uri-2",
 			Version:        "test-version-2",
@@ -410,6 +416,7 @@ cpes    = 1234
 		d := carton.BuildpackDependency{
 			BuildpackPath:  path,
 			ID:             "test-id",
+			Arch:           "amd64",
 			SHA256:         "test-sha256-2",
 			URI:            "test-uri-2",
 			Version:        "test-version-2",
@@ -463,6 +470,7 @@ version = "1.2.3"
 		d := carton.BuildpackDependency{
 			BuildpackPath:  path,
 			ID:             "test-id",
+			Arch:           "amd64",
 			SHA256:         "test-sha256-2",
 			URI:            "test-uri-2",
 			Version:        "test-version-2",
diff --git a/cmd/update-buildpack-dependency/main.go b/cmd/update-buildpack-dependency/main.go
index 4fcabe5..4645c5b 100644
--- a/cmd/update-buildpack-dependency/main.go
+++ b/cmd/update-buildpack-dependency/main.go
@@ -32,6 +32,7 @@ func main() {
 	flagSet := pflag.NewFlagSet("Update Buildpack Dependency", pflag.ExitOnError)
 	flagSet.StringVar(&b.BuildpackPath, "buildpack-toml", "", "path to buildpack.toml")
 	flagSet.StringVar(&b.ID, "id", "", "the id of the dependency")
+	flagSet.StringVar(&b.Arch, "arch", "", "the arch of the dependency")
 	flagSet.StringVar(&b.SHA256, "sha256", "", "the new sha256 of the dependency")
 	flagSet.StringVar(&b.URI, "uri", "", "the new uri of the dependency")
 	flagSet.StringVar(&b.Version, "version", "", "the new version of the dependency")
@@ -55,6 +56,10 @@ func main() {
 		log.Fatal("id must be set")
 	}
 
+	if b.Arch == "" {
+		b.Arch = "amd64"
+	}
+
 	if b.SHA256 == "" {
 		log.Fatal("sha256 must be set")
 	}