diff --git a/docs/modules/Reader.ts.md b/docs/modules/Reader.ts.md
index c4d8c690ee..9d00e7948f 100644
--- a/docs/modules/Reader.ts.md
+++ b/docs/modules/Reader.ts.md
@@ -442,7 +442,7 @@ Changes the value of the local context during the execution of the action `ma` (
 **Signature**
 
 ```ts
-export declare const local: <R2, R1>(f: (r2: R2) => R1) => <A>(ma: Reader<R1, A>) => Reader<R2, A>
+export declare const local: <R1, R2 = R1>(f: (r2: R2) => R1) => <A>(ma: Reader<R1, A>) => Reader<R2, A>
 ```
 
 **Example**
diff --git a/docs/modules/ReaderEither.ts.md b/docs/modules/ReaderEither.ts.md
index a727db0f9d..7cc4f07434 100644
--- a/docs/modules/ReaderEither.ts.md
+++ b/docs/modules/ReaderEither.ts.md
@@ -661,7 +661,9 @@ Changes the value of the local context during the execution of the action `ma` (
 **Signature**
 
 ```ts
-export declare const local: <R2, R1>(f: (r2: R2) => R1) => <E, A>(ma: ReaderEither<R1, E, A>) => ReaderEither<R2, E, A>
+export declare const local: <R1, R2 = R1>(
+  f: (r2: R2) => R1
+) => <E, A>(ma: ReaderEither<R1, E, A>) => ReaderEither<R2, E, A>
 ```
 
 Added in v2.0.0
diff --git a/docs/modules/ReaderTask.ts.md b/docs/modules/ReaderTask.ts.md
index e136ea5756..9b6eb583bc 100644
--- a/docs/modules/ReaderTask.ts.md
+++ b/docs/modules/ReaderTask.ts.md
@@ -441,7 +441,7 @@ Changes the value of the local context during the execution of the action `ma` (
 **Signature**
 
 ```ts
-export declare const local: <R2, R1>(f: (r2: R2) => R1) => <A>(ma: ReaderTask<R1, A>) => ReaderTask<R2, A>
+export declare const local: <R1, R2 = R1>(f: (r2: R2) => R1) => <A>(ma: ReaderTask<R1, A>) => ReaderTask<R2, A>
 ```
 
 Added in v2.3.0
diff --git a/docs/modules/ReaderTaskEither.ts.md b/docs/modules/ReaderTaskEither.ts.md
index 8ee8486229..2b08d60895 100644
--- a/docs/modules/ReaderTaskEither.ts.md
+++ b/docs/modules/ReaderTaskEither.ts.md
@@ -1032,7 +1032,7 @@ Changes the value of the local context during the execution of the action `ma` (
 **Signature**
 
 ```ts
-export declare const local: <R2, R1>(
+export declare const local: <R1, R2 = R1>(
   f: (r2: R2) => R1
 ) => <E, A>(ma: ReaderTaskEither<R1, E, A>) => ReaderTaskEither<R2, E, A>
 ```
diff --git a/docs/modules/StateReaderTaskEither.ts.md b/docs/modules/StateReaderTaskEither.ts.md
index 8d7cf0813e..25daa96565 100644
--- a/docs/modules/StateReaderTaskEither.ts.md
+++ b/docs/modules/StateReaderTaskEither.ts.md
@@ -903,7 +903,7 @@ Changes the value of the local context during the execution of the action `ma` (
 **Signature**
 
 ```ts
-export declare const local: <R2, R1>(
+export declare const local: <R1, R2 = R1>(
   f: (r2: R2) => R1
 ) => <S, E, A>(ma: StateReaderTaskEither<S, R1, E, A>) => StateReaderTaskEither<S, R2, E, A>
 ```
diff --git a/dtslint/ts3.5/Reader.ts b/dtslint/ts3.5/Reader.ts
index fb3081eb9c..1dc3e3a300 100644
--- a/dtslint/ts3.5/Reader.ts
+++ b/dtslint/ts3.5/Reader.ts
@@ -1,6 +1,26 @@
 import * as _ from '../../src/Reader'
 import { pipe } from '../../src/function'
 
+//
+// local
+//
+
+// $ExpectType Reader<{ a: string; }, string>
+pipe(
+  _.of<{ a: string }, string>('a'),
+  _.local((env) => ({
+    a: env.a
+  }))
+)
+
+// $ExpectType Reader<{ b: string; }, string>
+pipe(
+  _.of<{ a: string }, string>('a'),
+  _.local((env: { b: string }) => ({
+    a: env.b
+  }))
+)
+
 //
 // chainW
 //
diff --git a/dtslint/ts3.5/ReaderEither.ts b/dtslint/ts3.5/ReaderEither.ts
index 459e2d955c..7150d4285c 100644
--- a/dtslint/ts3.5/ReaderEither.ts
+++ b/dtslint/ts3.5/ReaderEither.ts
@@ -3,6 +3,26 @@ import * as R from '../../src/Reader'
 import * as E from '../../src/Either'
 import { pipe } from '../../src/function'
 
+//
+// local
+//
+
+// $ExpectType ReaderEither<{ a: string; }, number, string>
+pipe(
+  _.of<{ a: string }, number, string>('a'),
+  _.local((env) => ({
+    a: env.a
+  }))
+)
+
+// $ExpectType ReaderEither<{ b: string; }, number, string>
+pipe(
+  _.of<{ a: string }, number, string>('a'),
+  _.local((env: { b: string }) => ({
+    a: env.b
+  }))
+)
+
 //
 // getOrElseW
 //
diff --git a/dtslint/ts3.5/ReaderTask.ts b/dtslint/ts3.5/ReaderTask.ts
index ce12aa9dd4..3d89bd4383 100644
--- a/dtslint/ts3.5/ReaderTask.ts
+++ b/dtslint/ts3.5/ReaderTask.ts
@@ -1,6 +1,26 @@
 import * as _ from '../../src/ReaderTask'
 import { pipe } from '../../src/function'
 
+//
+// local
+//
+
+// $ExpectType ReaderTask<{ a: string; }, string>
+pipe(
+  _.of<{ a: string }, string>('a'),
+  _.local((env) => ({
+    a: env.a
+  }))
+)
+
+// $ExpectType ReaderTask<{ b: string; }, string>
+pipe(
+  _.of<{ a: string }, string>('a'),
+  _.local((env: { b: string }) => ({
+    a: env.b
+  }))
+)
+
 //
 // Do
 //
diff --git a/dtslint/ts3.5/ReaderTaskEither.ts b/dtslint/ts3.5/ReaderTaskEither.ts
index a95b22573d..1b2ff051db 100644
--- a/dtslint/ts3.5/ReaderTaskEither.ts
+++ b/dtslint/ts3.5/ReaderTaskEither.ts
@@ -5,6 +5,26 @@ import * as TE from '../../src/TaskEither'
 import * as IOE from '../../src/IOEither'
 import { pipe } from '../../src/function'
 
+//
+// local
+//
+
+// $ExpectType ReaderTaskEither<{ a: string; }, number, string>
+pipe(
+  _.of<{ a: string }, number, string>('a'),
+  _.local((env) => ({
+    a: env.a
+  }))
+)
+
+// $ExpectType ReaderTaskEither<{ b: string; }, number, string>
+pipe(
+  _.of<{ a: string }, number, string>('a'),
+  _.local((env: { b: string }) => ({
+    a: env.b
+  }))
+)
+
 //
 // getOrElseW
 //
diff --git a/dtslint/ts3.5/StateReaderTaskEither.ts b/dtslint/ts3.5/StateReaderTaskEither.ts
index 2583a8fc24..8fb0c55341 100644
--- a/dtslint/ts3.5/StateReaderTaskEither.ts
+++ b/dtslint/ts3.5/StateReaderTaskEither.ts
@@ -5,6 +5,26 @@ import * as RTE from '../../src/ReaderTaskEither'
 import * as IOE from '../../src/IOEither'
 import { pipe } from '../../src/function'
 
+//
+// local
+//
+
+// $ExpectType StateReaderTaskEither<boolean, { a: string; }, number, string>
+pipe(
+  _.of<boolean, { a: string }, number, string>('a'),
+  _.local((env) => ({
+    a: env.a
+  }))
+)
+
+// $ExpectType StateReaderTaskEither<boolean, { b: string; }, number, string>
+pipe(
+  _.of<boolean, { a: string }, number, string>('a'),
+  _.local((env: { b: string }) => ({
+    a: env.b
+  }))
+)
+
 //
 // chainW
 //
diff --git a/src/Reader.ts b/src/Reader.ts
index 486fe1494e..44e88fcf04 100644
--- a/src/Reader.ts
+++ b/src/Reader.ts
@@ -123,7 +123,7 @@ export const asks: <R, A>(f: (r: R) => A) => Reader<R, A> = identity
  * @category combinators
  * @since 2.0.0
  */
-export const local: <R2, R1>(f: (r2: R2) => R1) => <A>(ma: Reader<R1, A>) => Reader<R2, A> = (f) => (ma) => (r2) =>
+export const local: <R1, R2 = R1>(f: (r2: R2) => R1) => <A>(ma: Reader<R1, A>) => Reader<R2, A> = (f) => (ma) => (r2) =>
   ma(f(r2))
 
 /**
diff --git a/src/ReaderEither.ts b/src/ReaderEither.ts
index 5274493394..7779fc5af1 100644
--- a/src/ReaderEither.ts
+++ b/src/ReaderEither.ts
@@ -217,7 +217,7 @@ export const toUnion: <R, E, A>(fa: ReaderEither<R, E, A>) => Reader<R, E | A> =
  * @category combinators
  * @since 2.0.0
  */
-export const local: <R2, R1>(f: (r2: R2) => R1) => <E, A>(ma: ReaderEither<R1, E, A>) => ReaderEither<R2, E, A> =
+export const local: <R1, R2 = R1>(f: (r2: R2) => R1) => <E, A>(ma: ReaderEither<R1, E, A>) => ReaderEither<R2, E, A> =
   R.local
 
 /**
diff --git a/src/ReaderTask.ts b/src/ReaderTask.ts
index 7e2cba52f1..ad39888375 100644
--- a/src/ReaderTask.ts
+++ b/src/ReaderTask.ts
@@ -86,7 +86,7 @@ export const fromIO: FromIO2<URI>['fromIO'] = /*#__PURE__*/ flow(T.fromIO, fromT
  * @category combinators
  * @since 2.3.0
  */
-export const local: <R2, R1>(f: (r2: R2) => R1) => <A>(ma: ReaderTask<R1, A>) => ReaderTask<R2, A> = R.local
+export const local: <R1, R2 = R1>(f: (r2: R2) => R1) => <A>(ma: ReaderTask<R1, A>) => ReaderTask<R2, A> = R.local
 
 /**
  * Less strict version of [`asksReaderTask`](#asksreadertask).
diff --git a/src/ReaderTaskEither.ts b/src/ReaderTaskEither.ts
index c3659b0063..990e319164 100644
--- a/src/ReaderTaskEither.ts
+++ b/src/ReaderTaskEither.ts
@@ -350,7 +350,7 @@ export const chainNullableK: <E>(
  * @category combinators
  * @since 2.0.0
  */
-export const local: <R2, R1>(
+export const local: <R1, R2 = R1>(
   f: (r2: R2) => R1
 ) => <E, A>(ma: ReaderTaskEither<R1, E, A>) => ReaderTaskEither<R2, E, A> = R.local
 
diff --git a/src/StateReaderTaskEither.ts b/src/StateReaderTaskEither.ts
index 79957a436f..5e9f1c4ca7 100644
--- a/src/StateReaderTaskEither.ts
+++ b/src/StateReaderTaskEither.ts
@@ -234,7 +234,7 @@ export const fromReaderTaskEither: NaturalTransformation34<RTE.URI, URI> = /*#__
  * @category combinators
  * @since 2.11.0
  */
-export const local = <R2, R1>(f: (r2: R2) => R1) => <S, E, A>(
+export const local = <R1, R2 = R1>(f: (r2: R2) => R1) => <S, E, A>(
   ma: StateReaderTaskEither<S, R1, E, A>
 ): StateReaderTaskEither<S, R2, E, A> => flow(ma, R.local(f))