diff --git a/src/bump/bump-check.test.ts b/src/bump/bump-check.test.ts
new file mode 100644
index 0000000..8bdb796
--- /dev/null
+++ b/src/bump/bump-check.test.ts
@@ -0,0 +1,61 @@
+import chalk from "chalk";
+import latestVersion from "latest-version";
+
+import { bumpCheck } from "./bump-check";
+
+import { BumpObject } from "./interfaces/bump-object";
+
+describe("Bump check", () => {
+  let results: any;
+
+  beforeEach(() => {
+    results = [];
+    jest
+      .spyOn(process.stdout, "write")
+      .mockImplementation(val => results.push(String(val).trim()));
+  });
+
+  afterEach(() => jest.restoreAllMocks());
+
+  test("No updates needed", async () => {
+    jest.spyOn(latestVersion, "default").mockResolvedValue("1.0.0");
+
+    const validList: BumpObject[] = [
+      {
+        packageFile: { name: "test-1", version: "1.0.0" },
+        packagePath: "src/test",
+        bumpedVersion: "1.0.1",
+      },
+    ];
+
+    const checkedList = await bumpCheck(validList);
+    expect(checkedList).toEqual(validList);
+  });
+
+  test("Updates needed", async () => {
+    jest.spyOn(latestVersion, "default").mockResolvedValue("1.0.1");
+
+    const bumpList: BumpObject[] = [
+      {
+        packageFile: { name: "test-1", version: "1.0.0" },
+        packagePath: "src/test",
+        bumpedVersion: "1.0.1",
+      },
+    ];
+    const validList: BumpObject[] = [
+      {
+        packageFile: { name: "test-1", version: "1.0.0" },
+        packagePath: "src/test",
+        bumpedVersion: "1.0.2",
+      },
+    ];
+
+    const checkedList = await bumpCheck(bumpList);
+    expect(checkedList).toEqual(validList);
+    expect(results).toEqual(
+      chalk.red(
+        "test-1 version mismatch. NPM version 1.0.1. Bump value 1.0.1. Auto-bumping..."
+      )
+    );
+  });
+});
diff --git a/src/bump/bump-check.ts b/src/bump/bump-check.ts
new file mode 100644
index 0000000..2d04651
--- /dev/null
+++ b/src/bump/bump-check.ts
@@ -0,0 +1,56 @@
+import chalk from "chalk";
+import latestVersion from "latest-version";
+import PQueue from "p-queue";
+import semver from "semver";
+
+import { bumpValue } from "./bump-value";
+import log from "../utils/log";
+
+import { BumpObject } from "./interfaces/bump-object";
+
+const queue = new PQueue({ concurrency: 6 });
+
+const validate = async (item: BumpObject) => {
+  let npmVersion: string | boolean;
+
+  try {
+    // Get latest version from NPM registry and compare if bumped version is greater than NPM
+    npmVersion = await latestVersion(item.packageFile.name);
+    if (semver.gt(item.bumpedVersion, npmVersion)) {
+      return item;
+    }
+  } catch {
+    // Assume package isn't published on NPM yet
+    return item;
+  }
+
+  // If bumped value is not greater than NPM, auto bump with patch
+  const newItem = item;
+  const newVersion = bumpValue(npmVersion, "patch");
+  if (newVersion) {
+    newItem.bumpedVersion = newVersion;
+    return newItem;
+  }
+
+  // If failed to bump again, will not publish
+  newItem.failedValidation = true;
+  log(
+    chalk.red(
+      `${newItem.packageFile.name} version mismatch. Failed to bump. Not publishing.`
+    )
+  );
+  return newItem;
+};
+
+const bumpCheck = async (bumpList: BumpObject[]): Promise<BumpObject[]> => {
+  const checkedList: Promise<BumpObject>[] = [];
+
+  for (const item of bumpList) {
+    const validatedItem = queue.add(() => validate(item));
+    checkedList.push(validatedItem);
+  }
+
+  return Promise.all(checkedList);
+};
+
+export { bumpCheck };
diff --git a/src/bump/bump-value.test.ts b/src/bump/bump-value.test.ts
new file mode 100644
index 0000000..17aa4df
--- /dev/null
+++ b/src/bump/bump-value.test.ts
@@ -0,0 +1,28 @@
+import { bumpValue } from "./bump-value";
+
+describe("Bump Value", () => {
+  test("Patch", () => {
+    const newVersion = bumpValue("1.0.0", "patch");
+    expect(newVersion).toBe("1.0.1");
+  });
+
+  test("Minor", () => {
+    const newVersion = bumpValue("1.0.0", "minor");
+    expect(newVersion).toBe("1.1.0");
+  });
+
+  test("Major", () => {
+    const newVersion = bumpValue("1.0.0", "major");
+    expect(newVersion).toBe("2.0.0");
+  });
+
+  test("Version number", () => {
+    const newVersion = bumpValue("1.0.0", "2.5.1");
+    expect(newVersion).toBe("2.5.1");
+  });
+
+  test("False", () => {
+    const newVersion = bumpValue("a.b.c", "major");
+    expect(newVersion).toBeFalsy();
+  });
+});
diff --git a/src/bump/bump-value.ts b/src/bump/bump-value.ts
new file mode 100644
index 0000000..11c5638
--- /dev/null
+++ b/src/bump/bump-value.ts
@@ -0,0 +1,32 @@
+import semver from "semver";
+
+const bumpValue = (oldVersion: string, bumpArg: string): string | false => {
+  // Check if valid semver version and if invalid return false
+  const arr = semver.valid(oldVersion)?.split(".");
+  if (arr) {
+    if (bumpArg === "patch") {
+      const newNum = Number(arr[2]) + 1;
+      arr[2] = String(newNum);
+      return arr.join(".");
+    }
+    if (bumpArg === "minor") {
+      const newNum = Number(arr[1]) + 1;
+      arr[1] = String(newNum);
+      return arr.join(".");
+    }
+    if (bumpArg === "major") {
+      const newNum = Number(arr[0]) + 1;
+      arr[0] = String(newNum);
+      return arr.join(".");
+    }
+    // Else just return number version
+    if (semver.valid(bumpArg)) {
+      return bumpArg;
+    }
+
+    return false;
+  }
+  return false;
+};
+
+export { bumpValue };
diff --git a/src/bump/bump-write.test.ts b/src/bump/bump-write.test.ts
new file mode 100644
index 0000000..d737624
--- /dev/null
+++ b/src/bump/bump-write.test.ts
@@ -0,0 +1,25 @@
+import jsonfile from "jsonfile";
+
+import { bumpWrite } from "./bump-write";
+
+import { BumpObject } from "./interfaces/bump-object";
+
+describe("Bump write function", () => {
+  test("Should not throw", async () => {
+    jest.spyOn(jsonfile, "writeFile").mockResolvedValue();
+
+    const bumpList: BumpObject[] = [
+      {
+        packageFile: { name: "test-package", version: "1.0.0" },
+        packagePath: "src/publish/fixtures/",
+        bumpedVersion: "1.1.0",
+      },
+      {
+        packageFile: { name: "test-package2", version: "1.1.0" },
+        packagePath: "src/publish/fixtures/",
+        bumpedVersion: "1.2.0",
+      },
+    ];
+    await expect(bumpWrite(bumpList)).resolves.not.toThrow();
+  });
+});
diff --git a/src/bump/bump-write.ts b/src/bump/bump-write.ts
new file mode 100644
index 0000000..27734be
--- /dev/null
+++ b/src/bump/bump-write.ts
@@ -0,0 +1,24 @@
+import jsonfile from "jsonfile";
+import path from "path";
+
+import { BumpObject } from "./interfaces/bump-object";
+
+const writeUpdate = async (item: BumpObject) => {
+  const newPackageFile = item.packageFile;
+  newPackageFile.version = item.bumpedVersion;
+
+  await jsonfile.writeFile(
+    path.join(item.packagePath, "package.json"),
+    newPackageFile
+  );
+};
+
+const bumpWrite = (bumpList: BumpObject[]): Promise<void[]> => {
+  const promises = [];
+  for (const item of bumpList) {
+    promises.push(writeUpdate(item));
+  }
+  return Promise.all(promises);
+};
+
+export { bumpWrite };
diff --git a/src/bump/bump.ts b/src/bump/bump.ts
new file mode 100644
index 0000000..85a7327
--- /dev/null
+++ b/src/bump/bump.ts
@@ -0,0 +1,58 @@
+import async from "async";
+import chalk from "chalk";
+import latestVersion from "latest-version";
+import path from "path";
+import jsonfile from "jsonfile";
+import semver from "semver";
+
+import log from "../utils/log";
+import { pathToPackage } from "../utils/path-to-package";
+
+import { PackageJson } from "../utils/interfaces/package-json";
+import { QueueObject } from "./interfaces/queue-object";
+import { BumpObject } from "./interfaces/bump-object";
+
+const processQueue = async ({
+  packagePath,
+  packageFile,
+  bumpArg,
+  verify,
+}: QueueObject) => {
+  let npmVersion: string | false;
+  // Get latest version from NPM registry
+  try {
+    npmVersion = await latestVersion(packageFile.name);
+  } catch {
+    // Assume package isn't published
+    npmVersion = false;
+  }
+
+  // Bump current package.json
+  const currentVersion = packageFile.version;
+  const bumpedVersion = bumpValue(currentVersion, bumpArg);
+
+  if (bumpedVersion && npmVersion) {
+    // Compare if bumped version is greater than version on NPM
+    if (semver.gt(bumpedVersion, npmVersion)) {
+      await writeUpdate(packageFile, packagePath, bumpedVersion);
+    } else {
+      // Try bumping one more time this time
+      const newBumpedVersion = bumpValue(bumpedVersion, "patch");
+      if (newBumpedVersion && semver.gt(newBumpedVersion, npmVersion)) {
+        await writeUpdate(packageFile, packagePath, newBumpedVersion);
+      } else {
+        log(
+          chalk.red(
+            `${packageFile.name} failed to bump. Specified bump version is less than NPM version.`
+          )
+        );
+      }
+    }
+  } else {
+    log(
+      chalk.red(
+        `${packageFile.name} failed to bump. Possible failure due to bump value or incompatible existing package.json value.`
+      )
+    );
+  }
+};
diff --git a/src/bump/interfaces/bump-object.ts b/src/bump/interfaces/bump-object.ts
new file mode 100644
index 0000000..e0066f1
--- /dev/null
+++ b/src/bump/interfaces/bump-object.ts
@@ -0,0 +1,8 @@
+import { PackageJson } from "../../utils/interfaces/package-json";
+
+export interface BumpObject {
+  packageFile: PackageJson;
+  packagePath: string;
+  bumpedVersion: string;
+  failedValidation?: boolean;
+}
diff --git a/src/bump/interfaces/queue-object.ts b/src/bump/interfaces/queue-object.ts
new file mode 100644
index 0000000..fc9a8c1
--- /dev/null
+++ b/src/bump/interfaces/queue-object.ts
@@ -0,0 +1,8 @@
+import { PackageJson } from "../../utils/interfaces/package-json";
+
+export interface QueueObject {
+  packageFile: PackageJson;
+  packagePath: string;
+  bumpArg: string;
+  verify: boolean;
+}
diff --git a/src/changed/interfaces/config.ts b/src/changed/interfaces/config.ts
index 91f76d1..827a22a 100644
--- a/src/changed/interfaces/config.ts
+++ b/src/changed/interfaces/config.ts
@@ -4,4 +4,7 @@ export interface Config {
   commitMessage: string;
   commitFrom: string;
   commitTo?: string;
+  noVerify?: boolean;
+  autoBump?: boolean;
+  yes?: boolean;
 }
diff --git a/src/commands/bump.ts b/src/commands/bump.ts
index eb33931..edda2ba 100644
--- a/src/commands/bump.ts
+++ b/src/commands/bump.ts
@@ -1,4 +1,9 @@
 import { Command, flags } from "@oclif/command";
+import { cli } from "cli-ux";
+
+import chalk from "chalk";
+import { readConfig } from "../changed/read-config";
+import { findDiff } from "../changed/find-diff";
 
 export default class Bump extends Command {
   static description = "Bumps package versions";
@@ -9,11 +14,49 @@ export default class Bump extends Command {
     "no-verify": flags.boolean({
       description: "Skip checking NPM registry for conflicting versions",
     }),
+    // flag to patch auto-bump a package if version matches NPM version --auto-bump
+    "auto-bump": flags.boolean({
+      description: "Auto-bump package if specified version is too low",
+    }),
+    // flag to skip confirmation to write package bumps --yes
+    yes: flags.boolean({
+      description: "Skip confirmation to write bumped versions to package.json",
+    }),
   };
 
   static args = [{ name: "version" }];
 
   async run(): Promise<void> {
     const { args, flags } = this.parse(Bump);
+
+    const config = await readConfig();
+    const diff = await findDiff(config);
+
+    // Args
+    const bumpArg = args.version;
+
+    // Flags
+    let verify = true || config.noVerify;
+    if (flags["no-verify"]) verify = false;
+
+    let autoBump = false || config.autoBump;
+    if (flags["auto-bump"]) autoBump = true;
+
+    // If there are no packages to publish, no need for confirmation prompt
+    let skipPrompt = false || config.yes;
+    if (flags.yes) skipPrompt = true;
+
+    /* const bumpedFiles = await bumpList(diff, bumpArg, verify);
+    if (bumpedFiles) {
+      if (skipPrompt) {
+        await bumpPackages(bumpedFiles);
+      } else {
+        const input = await cli.confirm(`Bump ${bumpedFiles.length} packages?`);
+        if (input) {
+          await bumpPackages(bumpedFiles);
+          cli.log(chalk.green.bold(`Packages bumped!`));
+        }
+      }
+    } */
   }
 }
diff --git a/src/publish/bump.ts b/src/publish/bump.ts
deleted file mode 100644
index b39d1ab..0000000
--- a/src/publish/bump.ts
+++ /dev/null
@@ -1 +0,0 @@
-const bump = async diff => {};