diff --git a/.changeset/shiny-beans-wink.md b/.changeset/shiny-beans-wink.md
new file mode 100644
index 00000000000..f55f1eb6684
--- /dev/null
+++ b/.changeset/shiny-beans-wink.md
@@ -0,0 +1,5 @@
+---
+"@smithy/shared-ini-file-loader": patch
+---
+
+Allow dot, solidus, percent and colon characters in profile names
diff --git a/packages/shared-ini-file-loader/src/parseIni.spec.ts b/packages/shared-ini-file-loader/src/parseIni.spec.ts
index cf075b4659c..efa7ecc1ead 100644
--- a/packages/shared-ini-file-loader/src/parseIni.spec.ts
+++ b/packages/shared-ini-file-loader/src/parseIni.spec.ts
@@ -61,14 +61,21 @@ describe(parseIni.name, () => {
     // Some characters are not allowed in profile name, but we parse them as customers use them.
     // `@` https://github.com/awslabs/smithy-typescript/issues/1026
     // `+` https://github.com/aws/aws-sdk-js-v3/issues/5373
-    it.each(["-", "_", "@", "+"])("returns data for character '%s' in profile name", (specialChar: string) => {
-      const mockProfileName = ["profile", "stage"].join(specialChar);
-      const mockSectionFullName = ["profile", mockProfileName].join(" ");
-      const mockInput = getMockProfileContent(mockSectionFullName, mockProfileData);
-      expect(parseIni(mockInput)).toStrictEqual({
-        [["profile", mockProfileName].join(CONFIG_PREFIX_SEPARATOR)]: mockProfileData,
-      });
-    });
+    // `.` https://github.com/aws/aws-sdk-js-v3/issues/5449
+    // `/` https://github.com/awslabs/smithy-typescript/issues/1053
+    // `%` https://github.com/aws/aws-sdk-java-v2/pull/1538
+    // `:` https://github.com/aws/aws-sdk-java-v2/pull/1898
+    it.each(["-", "_", "@", "+", ".", "/", "%", ":"])(
+      "returns data for character '%s' in profile name",
+      (specialChar: string) => {
+        const mockProfileName = ["profile", "stage"].join(specialChar);
+        const mockSectionFullName = ["profile", mockProfileName].join(" ");
+        const mockInput = getMockProfileContent(mockSectionFullName, mockProfileData);
+        expect(parseIni(mockInput)).toStrictEqual({
+          [["profile", mockProfileName].join(CONFIG_PREFIX_SEPARATOR)]: mockProfileData,
+        });
+      }
+    );
 
     it("returns data for two profiles", () => {
       const mockProfile1 = getMockProfileContent(mockProfileName, mockProfileData);
diff --git a/packages/shared-ini-file-loader/src/parseIni.ts b/packages/shared-ini-file-loader/src/parseIni.ts
index afd28d01db1..b8c932c108a 100644
--- a/packages/shared-ini-file-loader/src/parseIni.ts
+++ b/packages/shared-ini-file-loader/src/parseIni.ts
@@ -2,7 +2,7 @@ import { IniSectionType, ParsedIniData } from "@smithy/types";
 
 import { CONFIG_PREFIX_SEPARATOR } from "./loadSharedConfigFiles";
 
-const prefixKeyRegex = /^([\w-]+)\s(["'])?([\w-@\+]+)\2$/;
+const prefixKeyRegex = /^([\w-]+)\s(["'])?([\w-@\+\.%:/]+)\2$/;
 const profileNameBlockList = ["__proto__", "profile __proto__"];
 
 export const parseIni = (iniData: string): ParsedIniData => {