diff --git a/packages/region/integration-tests/__tests__/region-module.spec.ts b/packages/region/integration-tests/__tests__/region-module.spec.ts
index 0a1871cf54..cf43c02bee 100644
--- a/packages/region/integration-tests/__tests__/region-module.spec.ts
+++ b/packages/region/integration-tests/__tests__/region-module.spec.ts
@@ -86,6 +86,87 @@ describe("Region Module Service", () => {
     )
   })
 
+  it("should create a region with countries", async () => {
+    const createdRegion = await service.create({
+      name: "North America",
+      currency_code: "USD",
+      countries: ["us", "ca"],
+    })
+
+    const region = await service.retrieve(createdRegion.id, {
+      relations: ["countries", "currency"],
+    })
+
+    expect(region).toEqual(
+      expect.objectContaining({
+        id: region.id,
+        name: "North America",
+        currency_code: "usd",
+        currency: expect.objectContaining({
+          code: "usd",
+          name: "US Dollar",
+        }),
+        countries: [
+          expect.objectContaining({
+            display_name: "Canada",
+            iso_2: "ca",
+          }),
+          expect.objectContaining({
+            display_name: "United States",
+            iso_2: "us",
+          }),
+        ],
+      })
+    )
+  })
+
+  it("should throw when country doesn't exist", async () => {
+    await expect(
+      service.create({
+        name: "North America",
+        currency_code: "USD",
+        countries: ["neverland"],
+      })
+    ).rejects.toThrowError("Countries with codes neverland does not exist")
+  })
+
+  it("should throw when country is already assigned to a region", async () => {
+    await service.create({
+      name: "North America",
+      currency_code: "USD",
+      countries: ["us"],
+    })
+
+    await expect(
+      service.create({
+        name: "United States",
+        currency_code: "USD",
+        countries: ["us"],
+      })
+    ).rejects.toThrowError(
+      "Country with code us is already assigned to a region"
+    )
+  })
+
+  it("should throw when country is being assigned to multiple regions", async () => {
+    await expect(
+      service.create([
+        {
+          name: "United States",
+          currency_code: "USD",
+          countries: ["us"],
+        },
+        {
+          name: "North America",
+          currency_code: "USD",
+          countries: ["us"],
+        },
+      ])
+    ).rejects.toThrowError(
+      "Country with code us is already assigned to a region"
+    )
+  })
+
   it("should fail when currency does not exist", async () => {
     await expect(
       service.create({
diff --git a/packages/region/src/models/country.ts b/packages/region/src/models/country.ts
index 4f65828288..9df8d781c6 100644
--- a/packages/region/src/models/country.ts
+++ b/packages/region/src/models/country.ts
@@ -30,13 +30,15 @@ export default class Country {
   @Property({ columnType: "text" })
   display_name: string
 
+  @Property({ columnType: "text", nullable: true })
+  region_id?: string | null = null
+
   @ManyToOne({
     entity: () => Region,
-    fieldName: "region_id",
     index: "IDX_country_region_id",
     nullable: true,
   })
-  region: Region | null = null
+  region?: Region | null
 
   @BeforeCreate()
   onCreate() {
diff --git a/packages/region/src/services/region-module.ts b/packages/region/src/services/region-module.ts
index d39c18745d..0089b06c54 100644
--- a/packages/region/src/services/region-module.ts
+++ b/packages/region/src/services/region-module.ts
@@ -23,7 +23,11 @@ import {
 import { Country, Currency, Region } from "@models"
 
 import { DefaultsUtils } from "@medusajs/utils"
-import { CreateCountryDTO, CreateCurrencyDTO } from "@types"
+import {
+  CreateCountryDTO,
+  CreateCurrencyDTO,
+  CreateRegionDTO as InternalCreateRegionDTO,
+} from "@types"
 import { entityNameToLinkableKeysMap, joinerConfig } from "../joiner-config"
 
 const COUNTRIES_LIMIT = 1000
@@ -115,20 +119,70 @@ export default class RegionModuleService<
       sharedContext
     )
 
-    let currencyMap = new Map(currencies.map((c) => [c.code.toLowerCase(), c]))
-    for (const reg of data) {
-      const lowerCasedCurrency = reg.currency_code.toLowerCase()
+    const countriesInDb = await this.countryService_.list(
+      { iso_2: data.map((d) => d.countries).flat() },
+      { select: ["iso_2", "region_id"] },
+      sharedContext
+    )
+
+    const countriesInDbMap = new Map<string, Country>(
+      countriesInDb.map((c) => [c.iso_2, c])
+    )
+
+    const currencyMap = new Map(
+      currencies.map((c) => [c.code.toLowerCase(), c])
+    )
+
+    const toCreate: InternalCreateRegionDTO[] = []
+    const seenCountries = new Set<string>()
+    for (const region of data) {
+      const reg = { ...region } as InternalCreateRegionDTO
+      const countriesToAdd = region.countries || []
+
+      if (countriesToAdd) {
+        const notInDb = countriesToAdd.filter(
+          (c) => !countriesInDbMap.has(c.toLowerCase())
+        )
+
+        if (notInDb.length) {
+          throw new MedusaError(
+            MedusaError.Types.INVALID_DATA,
+            `Countries with codes ${countriesToAdd.join(", ")} does not exist`
+          )
+        }
+
+        const regionCountries = countriesToAdd.map((code) => {
+          const country = countriesInDbMap.get(code.toLowerCase())
+
+          if (country?.region_id || seenCountries.has(code.toLowerCase())) {
+            throw new MedusaError(
+              MedusaError.Types.INVALID_DATA,
+              `Country with code ${code} is already assigned to a region`
+            )
+          }
+
+          seenCountries.add(code.toLowerCase())
+
+          return country
+        }) as unknown as TCountry[]
+
+        reg.countries = regionCountries
+      }
+
+      const lowerCasedCurrency = region.currency_code.toLowerCase()
       if (!currencyMap.has(lowerCasedCurrency)) {
         throw new MedusaError(
           MedusaError.Types.INVALID_DATA,
-          `Currency with code: ${reg.currency_code} was not found`
+          `Currency with code: ${region.currency_code} was not found`
         )
       }
 
       reg.currency_code = lowerCasedCurrency
+
+      toCreate.push(reg as InternalCreateRegionDTO)
     }
 
-    const result = await this.regionService_.create(data, sharedContext)
+    const result = await this.regionService_.create(toCreate, sharedContext)
 
     return result
   }
diff --git a/packages/region/src/types/index.ts b/packages/region/src/types/index.ts
index 66a2deb8e0..c1841fd471 100644
--- a/packages/region/src/types/index.ts
+++ b/packages/region/src/types/index.ts
@@ -1,4 +1,5 @@
 import { Logger } from "@medusajs/types"
+import { Country } from "@models"
 
 export type InitializeModuleInjectableDependencies = {
   logger?: Logger
@@ -22,4 +23,10 @@ export type CreateCountryDTO = {
   num_code: string
   name: string
   display_name: string
+}
+
+export type CreateRegionDTO = {
+  name: string
+  currency_code: string
+  countries?: Country[]
 }
\ No newline at end of file
diff --git a/packages/types/src/region/mutations.ts b/packages/types/src/region/mutations.ts
index 2ce1ba27b8..4b429dfcbc 100644
--- a/packages/types/src/region/mutations.ts
+++ b/packages/types/src/region/mutations.ts
@@ -4,6 +4,7 @@ export interface CreateRegionDTO {
   name: string
   currency_code: string
   currency?: RegionCurrencyDTO
+  countries?: string[]
   tax_code?: string
   tax_rate?: number
   tax_provider_id?: string
@@ -13,6 +14,7 @@ export interface UpdateRegionDTO {
   id: string
   currency_code?: string
   currency?: RegionCurrencyDTO
+  countries: string[]
   name?: string
   tax_code?: string
   tax_rate?: number