diff --git a/README.md b/README.md
index 9f36c75..ceac696 100644
--- a/README.md
+++ b/README.md
@@ -3,6 +3,7 @@
 This action will create a github release and optionally upload an artifact to it.
 
 ## Action Inputs
+- **allowUpdates**: An optional flag which indicates if we should update a release if it already exists. Defaults to false.
 - **artifact**: An optional set of paths representing artifacts to upload to the release. This may be a single path or a comma delimited list of paths (or globs).
 - **artifacts**: An optional set of paths representing artifacts to upload to the release. This may be a single path or a comma delimited list of paths (or globs).
 - **artifactContentType**: The content type of the artifact. Defaults to raw.
diff --git a/__tests__/Action.test.ts b/__tests__/Action.test.ts
index 3c3ea6c..a2c663d 100644
--- a/__tests__/Action.test.ts
+++ b/__tests__/Action.test.ts
@@ -5,6 +5,8 @@ import { Releases } from "../src/Releases";
 import { ArtifactUploader } from "../src/ArtifactUploader";
 
 const createMock = jest.fn()
+const getMock = jest.fn()
+const updateMock = jest.fn()
 const uploadMock = jest.fn()
 
 const artifacts = [
@@ -14,9 +16,8 @@ const artifacts = [
 const artifactData = Buffer.from('blob', 'utf-8')
 const body = 'body'
 const commit = 'commit'
-const contentType = "raw"
-const contentLength = 100
 const draft = true
+const id = 100
 const name = 'name'
 const tag = 'tag'
 const token = 'token'
@@ -25,11 +26,13 @@ const url = 'http://api.example.com'
 describe("Action", () => {
     beforeEach(() => {
         createMock.mockClear()
+        getMock.mockClear()
+        updateMock.mockClear()
         uploadMock.mockClear()
     })
 
     it('creates release but does not upload if no artifact', async () => {
-        const action = createAction(false)
+        const action = createAction(false, false)
 
         await action.perform()
 
@@ -38,12 +41,7 @@ describe("Action", () => {
     })
 
     it('creates release then uploads artifact', async () => {
-        const action = createAction(true)
-        createMock.mockResolvedValue({
-            data: {
-                upload_url: url
-            }
-        })
+        const action = createAction(false, true)
 
         await action.perform()
 
@@ -52,7 +50,7 @@ describe("Action", () => {
     })
 
     it('throws error when create fails', async () => {
-        const action = createAction(true)
+        const action = createAction(false, true)
         createMock.mockRejectedValue("error")
 
         expect.hasAssertions()
@@ -66,13 +64,56 @@ describe("Action", () => {
         expect(uploadMock).not.toBeCalled()
     })
 
+    it('throws error when get fails', async () => {
+        const action = createAction(true, false)
+        const error = {
+            errors: [
+                {
+                    code: 'already_exists'
+                }
+            ]
+        }
+        
+        createMock.mockRejectedValue(error)
+        getMock.mockRejectedValue("error")
+        expect.hasAssertions()
+        try {
+            await action.perform()
+        } catch (error) {
+            expect(error).toEqual("error")
+        }
+        
+        expect(createMock).toBeCalledWith(tag, body, commit, draft, name)
+        expect(uploadMock).not.toBeCalled()
+        
+    })
+
+    it('throws error when update fails', async () => {
+        const action = createAction(true, false)
+        const error = {
+            errors: [
+                {
+                    code: 'already_exists'
+                }
+            ]
+        }
+        
+        createMock.mockRejectedValue(error)
+        updateMock.mockRejectedValue("error")
+        expect.hasAssertions()
+        try {
+            await action.perform()
+        } catch (error) {
+            expect(error).toEqual("error")
+        }
+        
+        expect(createMock).toBeCalledWith(tag, body, commit, draft, name)
+        expect(uploadMock).not.toBeCalled()
+        
+    })
+
     it('throws error when upload fails', async () => {
-        const action = createAction(true)
-        createMock.mockResolvedValue({
-            data: {
-                upload_url: url
-            }
-        })
+        const action = createAction(false, true)
         uploadMock.mockRejectedValue("error")
 
         expect.hasAssertions()
@@ -86,7 +127,45 @@ describe("Action", () => {
         expect(uploadMock).toBeCalledWith(artifacts, url)
     })
 
-    function createAction(hasArtifact: boolean): Action {
+    it('updates release but does not upload if no artifact', async () => {
+        const action = createAction(true, false)
+        const error = {
+            errors: [
+                {
+                    code: 'already_exists'
+                }
+            ]
+        }
+        
+        createMock.mockRejectedValue(error)
+
+        await action.perform()
+        
+        expect(createMock).toBeCalledWith(tag, body, commit, draft, name)
+        expect(uploadMock).not.toBeCalled()
+        
+    })
+
+    it('updates release then uploads artifact', async () => {
+        const action = createAction(true, true)
+        const error = {
+            errors: [
+                {
+                    code: 'already_exists'
+                }
+            ]
+        }
+        
+        createMock.mockRejectedValue(error)
+
+        await action.perform()
+        
+        expect(createMock).toBeCalledWith(tag, body, commit, draft, name)
+        expect(uploadMock).toBeCalledWith(artifacts, url)
+        
+    })
+
+    function createAction(allowUpdates: boolean, hasArtifact: boolean): Action {
         let inputArtifact: Artifact[]
         if (hasArtifact) {
             inputArtifact = artifacts
@@ -96,11 +175,32 @@ describe("Action", () => {
         const MockReleases = jest.fn<Releases, any>(() => {
             return {
                 create: createMock,
-                uploadArtifact: jest.fn()
+                getByTag: getMock,
+                update: updateMock,
+                uploadArtifact: uploadMock
             }
         })
+
+        createMock.mockResolvedValue({
+            data: {
+                upload_url: url
+            }
+        })
+        getMock.mockResolvedValue({
+            data: {
+                id: id
+            }
+        })
+        updateMock.mockResolvedValue({
+            data: {
+                upload_url: url
+            }
+        })
+        uploadMock.mockResolvedValue({})
+
         const MockInputs = jest.fn<Inputs, any>(() => {
             return {
+                allowUpdates: allowUpdates,
                 artifacts: inputArtifact,
                 body: body,
                 commit: commit,
diff --git a/__tests__/ErrorMessage.test.ts b/__tests__/ErrorMessage.test.ts
index 3073e0b..65596b4 100644
--- a/__tests__/ErrorMessage.test.ts
+++ b/__tests__/ErrorMessage.test.ts
@@ -1,6 +1,33 @@
 import { ErrorMessage } from "../src/ErrorMessage"
 
 describe('ErrorMessage', () => {
+
+    describe('has error with code', () => {
+        const error = {
+            message: 'something bad happened',
+            errors: [
+                {
+                    code: 'missing',
+                    resource: 'release'
+                },
+                {
+                    code: 'already_exists',
+                    resource: 'release'
+                }
+            ]
+        }
+
+        it('does not have error', ()=> {
+            const errorMessage = new ErrorMessage(error)
+            expect(errorMessage.hasErrorWithCode('missing_field')).toBeFalsy()
+        })
+
+        it('has error', ()=> {
+            const errorMessage = new ErrorMessage(error)
+            expect(errorMessage.hasErrorWithCode('missing')).toBeTruthy()
+        })
+    })
+
     it('generates message with errors', () => {
         const resource = "release"
         const error = {
diff --git a/__tests__/GithubError.test.ts b/__tests__/GithubError.test.ts
index 70906dc..657a756 100644
--- a/__tests__/GithubError.test.ts
+++ b/__tests__/GithubError.test.ts
@@ -1,6 +1,17 @@
 import { GithubError } from "../src/GithubError"
 
 describe('GithubError', () => {
+
+    it('provides error code', () => {
+        const error = {
+            code: "missing"
+        }
+
+        const githubError = new GithubError(error)
+
+        expect(githubError.code).toBe('missing')
+    })
+
     it('generates missing resource error message', () => {
         const resource = "release"
         const error = {
@@ -66,10 +77,10 @@ describe('GithubError', () => {
                 message: "foo",
                 documentation_url: url
             }
-    
+
             const githubError = new GithubError(error)
             const message = githubError.toString()
-    
+
             expect(message).toBe(`foo\nPlease see ${url}.`)
         })
 
@@ -78,10 +89,10 @@ describe('GithubError', () => {
                 code: "custom",
                 message: "foo"
             }
-    
+
             const githubError = new GithubError(error)
             const message = githubError.toString()
-    
+
             expect(message).toBe('foo')
         })
     })
diff --git a/__tests__/Inputs.test.ts b/__tests__/Inputs.test.ts
index 79819da..a8d49e1 100644
--- a/__tests__/Inputs.test.ts
+++ b/__tests__/Inputs.test.ts
@@ -43,6 +43,17 @@ describe('Inputs', () => {
         expect(inputs.token).toBe('42')
     })
 
+    describe('allowsUpdates', () => {
+        it('returns false', () => {
+            expect(inputs.allowUpdates).toBe(false)
+        })
+
+        it('returns true', () => {
+            mockGetInput.mockReturnValue('true')
+            expect(inputs.allowUpdates).toBe(true)
+        })
+    })
+
     describe('artifacts', () => {
         it('returns empty artifacts', () => {
             mockGetInput.mockReturnValueOnce('')
diff --git a/action.yml b/action.yml
index c7ea266..34bc480 100644
--- a/action.yml
+++ b/action.yml
@@ -2,6 +2,9 @@ name: 'Create Release'
 description: 'Creates github releases'
 author: 'Nick Cipollo'
 inputs:
+  allowUpdates: 
+    description: 'An optional flag which indicates if we should update a release if it already exists. Defaults to false.'
+    default: ''
   artifact:
     description: 'An optional set of paths representing artifacts to upload to the release. This may be a single path or a comma delimited list of paths (or globs)'
     default: ''
diff --git a/src/Action.ts b/src/Action.ts
index 7c42da3..4f4d741 100644
--- a/src/Action.ts
+++ b/src/Action.ts
@@ -1,6 +1,8 @@
 import { Inputs } from "./Inputs";
 import { Releases } from "./Releases";
 import { ArtifactUploader } from "./ArtifactUploader";
+import { ErrorMessage } from "./ErrorMessage";
+import { Response, ReposCreateReleaseResponse } from "@octokit/rest";
 
 export class Action {
     private inputs: Inputs
@@ -14,7 +16,28 @@ export class Action {
     }
 
     async perform() {
-        const createResult = await this.releases.create(
+        const uploadUrl = await this.createOrUpdateRelease()
+
+        const artifacts = this.inputs.artifacts
+        if (artifacts.length > 0) {
+            await this.uploader.uploadArtifacts(artifacts, uploadUrl)
+        }
+    }
+
+    private async createOrUpdateRelease(): Promise<string> {
+        try {
+            return await this.createRelease()
+        } catch (error) {
+            if (this.releaseAlreadyExisted(error) && this.inputs.allowUpdates) {
+                return this.updateRelease()
+            } else {
+                throw error
+            }
+        }
+    }
+
+    private async createRelease(): Promise<string> {
+        const response = await this.releases.create(
             this.inputs.tag,
             this.inputs.body,
             this.inputs.commit,
@@ -22,12 +45,27 @@ export class Action {
             this.inputs.name
         )
 
-        const artifacts = this.inputs.artifacts
-        if (artifacts.length > 0) {
-            await this.uploader.uploadArtifacts(
-                artifacts,
-                createResult.data.upload_url
-            )
-        }
+        return response.data.upload_url
+    }
+
+    private releaseAlreadyExisted(error: any): boolean {
+        const errorMessage = new ErrorMessage(error)
+        return errorMessage.hasErrorWithCode('already_exists')
+    }
+
+    private async updateRelease(): Promise<string> {
+        const getResponse = await this.releases.getByTag(this.inputs.tag)
+        const id = getResponse.data.id
+
+        const response = await this.releases.update(
+            id,
+            this.inputs.tag,
+            this.inputs.body,
+            this.inputs.commit,
+            this.inputs.draft,
+            this.inputs.name
+        )
+
+        return response.data.upload_url
     }
 }
\ No newline at end of file
diff --git a/src/ArtifactUploader.ts b/src/ArtifactUploader.ts
index a6f7f7e..2cb234b 100644
--- a/src/ArtifactUploader.ts
+++ b/src/ArtifactUploader.ts
@@ -2,7 +2,7 @@ import { Artifact } from "./Artifact";
 import { Releases } from "./Releases";
 
 export interface ArtifactUploader {
-    uploadArtifacts(artifacts: Artifact[], uploadUrl: string): void
+    uploadArtifacts(artifacts: Artifact[], uploadUrl: string): Promise<void>
 }
 
 export class GithubArtifactUploader implements ArtifactUploader {
diff --git a/src/ErrorMessage.ts b/src/ErrorMessage.ts
index e10f440..63e7046 100644
--- a/src/ErrorMessage.ts
+++ b/src/ErrorMessage.ts
@@ -1,23 +1,15 @@
 import { GithubError } from "./GithubError"
 
 export class ErrorMessage {
-    error: any
+    private error: any
+    private githubErrors: GithubError[]
 
     constructor(error: any) {
         this.error = error
+        this.githubErrors = this.generateGithubErrors()
     }
 
-    toString(): string {
-        const message = this.error.message
-        const errors = this.githubErrors()
-        if (errors.length > 0) {
-            return `${message}\nErrors:\n${this.errorBulletedList(errors)}`
-        } else {
-            return message
-        }
-    }
-
-    githubErrors(): GithubError[] {
+    private generateGithubErrors(): GithubError[] {
         const errors = this.error.errors
         if (errors instanceof Array) {
             return errors.map((err) => new GithubError(err))
@@ -26,7 +18,21 @@ export class ErrorMessage {
         }
     }
 
-    errorBulletedList(errors: GithubError[]): string {
+    hasErrorWithCode(code: String): boolean {
+        return this.githubErrors.some((err) => err.code == code)
+    }
+
+    toString(): string {
+        const message = this.error.message
+        const errors = this.githubErrors
+        if (errors.length > 0) {
+            return `${message}\nErrors:\n${this.errorBulletedList(errors)}`
+        } else {
+            return message
+        }
+    }
+
+    private errorBulletedList(errors: GithubError[]): string {
         return errors.map((err) => `- ${err}`).join("\n")
     }
 }
diff --git a/src/GithubError.ts b/src/GithubError.ts
index 72fecd0..be2d29b 100644
--- a/src/GithubError.ts
+++ b/src/GithubError.ts
@@ -1,13 +1,17 @@
 export class GithubError {
-    error: any;
+    private error: any;
 
     constructor(error: any) {
         this.error = error
     }
 
+    get code(): string {
+        return this.error.code
+    }
+
     toString(): string {
-        const code = this.error.code 
-        switch(code) {
+        const code = this.error.code
+        switch (code) {
             case 'missing':
                 return this.missingResourceMessage()
             case 'missing_field':
@@ -26,7 +30,7 @@ export class GithubError {
         const documentation = this.error.documentation_url
 
         let documentationMessage: string
-        if(documentation) {
+        if (documentation) {
             documentationMessage = `\nPlease see ${documentation}.`
         } else {
             documentationMessage = ""
@@ -41,7 +45,7 @@ export class GithubError {
 
         return `The ${field} field on ${resource} is an invalid format.`
     }
-    
+
     private missingResourceMessage(): string {
         const resource = this.error.resource
         return `${resource} does not exist.`
diff --git a/src/Inputs.ts b/src/Inputs.ts
index 6dc0091..21c53d3 100644
--- a/src/Inputs.ts
+++ b/src/Inputs.ts
@@ -5,6 +5,7 @@ import { ArtifactGlobber } from './ArtifactGlobber';
 import { Artifact } from './Artifact';
 
 export interface Inputs {
+    readonly allowUpdates: boolean
     readonly artifacts: Artifact[]
     readonly body: string
     readonly commit: string
@@ -23,6 +24,11 @@ export class CoreInputs implements Inputs {
         this.context = context
     }
 
+    get allowUpdates(): boolean {
+        const allow = core.getInput('allowUpdates')
+        return allow == 'true'
+    }
+
     get artifacts(): Artifact[] {
         let artifacts = core.getInput('artifacts')
         if (!artifacts) {
diff --git a/src/Releases.ts b/src/Releases.ts
index 4b92cca..2ce99dc 100644
--- a/src/Releases.ts
+++ b/src/Releases.ts
@@ -1,6 +1,6 @@
 import { Context } from "@actions/github/lib/context";
 import { GitHub } from "@actions/github";
-import { AnyResponse, Response, ReposCreateReleaseResponse } from "@octokit/rest";
+import { AnyResponse, Response, ReposCreateReleaseResponse, ReposGetReleaseByTagResponse } from "@octokit/rest";
 
 export interface Releases {
     create(
@@ -11,6 +11,17 @@ export interface Releases {
         name?: string
     ): Promise<Response<ReposCreateReleaseResponse>>
 
+    getByTag(tag: string): Promise<Response<ReposGetReleaseByTagResponse>>
+
+    update(
+        id: number,
+        tag: string,
+        body?: string,
+        commitHash?: string,
+        draft?: boolean,
+        name?: string
+    ): Promise<Response<ReposCreateReleaseResponse>>
+
     uploadArtifact(
         assetUrl: string,
         contentLength: number,
@@ -20,7 +31,7 @@ export interface Releases {
     ): Promise<Response<AnyResponse>>
 }
 
-export class GithubReleases implements Releases{
+export class GithubReleases implements Releases {
     context: Context
     git: GitHub
 
@@ -47,6 +58,34 @@ export class GithubReleases implements Releases{
         })
     }
 
+    async getByTag(tag: string): Promise<Response<ReposGetReleaseByTagResponse>> {
+        return this.git.repos.getReleaseByTag({
+            owner: this.context.repo.owner,
+            repo: this.context.repo.repo,
+            tag: tag
+        })
+    }
+
+    async update(
+        id: number,
+        tag: string,
+        body?: string,
+        commitHash?: string,
+        draft?: boolean,
+        name?: string
+    ): Promise<Response<ReposCreateReleaseResponse>> {
+        return this.git.repos.updateRelease({
+            release_id: id,
+            body: body,
+            name: name,
+            draft: draft,
+            owner: this.context.repo.owner,
+            repo: this.context.repo.repo,
+            target_commitish: commitHash,
+            tag_name: tag
+        })
+    }
+
     async uploadArtifact(
         assetUrl: string,
         contentLength: number,