diff --git a/README.md b/README.md
index c133158e7..23f7977f3 100644
--- a/README.md
+++ b/README.md
@@ -224,7 +224,7 @@ It is possible to integrate this VPC module with [terraform-aws-transit-gateway
 
 | Name | Version |
 |------|---------|
-| terraform | >= 0.12.7 |
+| terraform | >= 0.12.21 |
 | aws | >= 2.68 |
 
 ## Providers
diff --git a/examples/complete-vpc/README.md b/examples/complete-vpc/README.md
index b5dd47274..385ec8d80 100644
--- a/examples/complete-vpc/README.md
+++ b/examples/complete-vpc/README.md
@@ -21,7 +21,7 @@ Note that this example may create resources which can cost money (AWS Elastic IP
 
 | Name | Version |
 |------|---------|
-| terraform | >= 0.12.7 |
+| terraform | >= 0.12.21 |
 | aws | >= 2.68 |
 
 ## Providers
diff --git a/examples/complete-vpc/versions.tf b/examples/complete-vpc/versions.tf
index 85a2050d0..f52cfcbc8 100644
--- a/examples/complete-vpc/versions.tf
+++ b/examples/complete-vpc/versions.tf
@@ -1,5 +1,5 @@
 terraform {
-  required_version = ">= 0.12.7"
+  required_version = ">= 0.12.21"
 
   required_providers {
     aws = ">= 2.68"
diff --git a/examples/ipv6/README.md b/examples/ipv6/README.md
index 8889b690a..f2a4f23f7 100644
--- a/examples/ipv6/README.md
+++ b/examples/ipv6/README.md
@@ -19,7 +19,7 @@ Note that this example may create resources which can cost money (AWS Elastic IP
 
 | Name | Version |
 |------|---------|
-| terraform | >= 0.12.7 |
+| terraform | >= 0.12.21 |
 | aws | >= 2.68 |
 
 ## Providers
diff --git a/examples/ipv6/versions.tf b/examples/ipv6/versions.tf
index 85a2050d0..f52cfcbc8 100644
--- a/examples/ipv6/versions.tf
+++ b/examples/ipv6/versions.tf
@@ -1,5 +1,5 @@
 terraform {
-  required_version = ">= 0.12.7"
+  required_version = ">= 0.12.21"
 
   required_providers {
     aws = ">= 2.68"
diff --git a/examples/issue-108-route-already-exists/README.md b/examples/issue-108-route-already-exists/README.md
index 1e154b3c3..02846d6be 100644
--- a/examples/issue-108-route-already-exists/README.md
+++ b/examples/issue-108-route-already-exists/README.md
@@ -23,7 +23,7 @@ Note that this example may create resources which can cost money (AWS Elastic IP
 
 | Name | Version |
 |------|---------|
-| terraform | >= 0.12.7 |
+| terraform | >= 0.12.21 |
 | aws | >= 2.68 |
 
 ## Providers
diff --git a/examples/issue-108-route-already-exists/versions.tf b/examples/issue-108-route-already-exists/versions.tf
index 85a2050d0..f52cfcbc8 100644
--- a/examples/issue-108-route-already-exists/versions.tf
+++ b/examples/issue-108-route-already-exists/versions.tf
@@ -1,5 +1,5 @@
 terraform {
-  required_version = ">= 0.12.7"
+  required_version = ">= 0.12.21"
 
   required_providers {
     aws = ">= 2.68"
diff --git a/examples/issue-44-asymmetric-private-subnets/README.md b/examples/issue-44-asymmetric-private-subnets/README.md
index 64d57b760..549a6037f 100644
--- a/examples/issue-44-asymmetric-private-subnets/README.md
+++ b/examples/issue-44-asymmetric-private-subnets/README.md
@@ -21,7 +21,7 @@ Note that this example may create resources which can cost money (AWS Elastic IP
 
 | Name | Version |
 |------|---------|
-| terraform | >= 0.12.7 |
+| terraform | >= 0.12.21 |
 | aws | >= 2.68 |
 
 ## Providers
diff --git a/examples/issue-44-asymmetric-private-subnets/versions.tf b/examples/issue-44-asymmetric-private-subnets/versions.tf
index 85a2050d0..f52cfcbc8 100644
--- a/examples/issue-44-asymmetric-private-subnets/versions.tf
+++ b/examples/issue-44-asymmetric-private-subnets/versions.tf
@@ -1,5 +1,5 @@
 terraform {
-  required_version = ">= 0.12.7"
+  required_version = ">= 0.12.21"
 
   required_providers {
     aws = ">= 2.68"
diff --git a/examples/issue-46-no-private-subnets/README.md b/examples/issue-46-no-private-subnets/README.md
index 78a7118e8..f93a23c1c 100644
--- a/examples/issue-46-no-private-subnets/README.md
+++ b/examples/issue-46-no-private-subnets/README.md
@@ -21,7 +21,7 @@ Note that this example may create resources which can cost money (AWS Elastic IP
 
 | Name | Version |
 |------|---------|
-| terraform | >= 0.12.7 |
+| terraform | >= 0.12.21 |
 | aws | >= 2.68 |
 
 ## Providers
diff --git a/examples/issue-46-no-private-subnets/versions.tf b/examples/issue-46-no-private-subnets/versions.tf
index 85a2050d0..f52cfcbc8 100644
--- a/examples/issue-46-no-private-subnets/versions.tf
+++ b/examples/issue-46-no-private-subnets/versions.tf
@@ -1,5 +1,5 @@
 terraform {
-  required_version = ">= 0.12.7"
+  required_version = ">= 0.12.21"
 
   required_providers {
     aws = ">= 2.68"
diff --git a/examples/manage-default-vpc/README.md b/examples/manage-default-vpc/README.md
index 0fae2dd8d..fa20d2aa4 100644
--- a/examples/manage-default-vpc/README.md
+++ b/examples/manage-default-vpc/README.md
@@ -21,7 +21,7 @@ Run `terraform destroy` when you don't need these resources.
 
 | Name | Version |
 |------|---------|
-| terraform | >= 0.12.7 |
+| terraform | >= 0.12.21 |
 | aws | >= 2.68 |
 
 ## Providers
diff --git a/examples/manage-default-vpc/versions.tf b/examples/manage-default-vpc/versions.tf
index 85a2050d0..f52cfcbc8 100644
--- a/examples/manage-default-vpc/versions.tf
+++ b/examples/manage-default-vpc/versions.tf
@@ -1,5 +1,5 @@
 terraform {
-  required_version = ">= 0.12.7"
+  required_version = ">= 0.12.21"
 
   required_providers {
     aws = ">= 2.68"
diff --git a/examples/network-acls/README.md b/examples/network-acls/README.md
index 35f420169..01eceba22 100644
--- a/examples/network-acls/README.md
+++ b/examples/network-acls/README.md
@@ -23,7 +23,7 @@ Note that this example may create resources which can cost money (AWS Elastic IP
 
 | Name | Version |
 |------|---------|
-| terraform | >= 0.12.7 |
+| terraform | >= 0.12.21 |
 | aws | >= 2.68 |
 
 ## Providers
diff --git a/examples/network-acls/versions.tf b/examples/network-acls/versions.tf
index 85a2050d0..f52cfcbc8 100644
--- a/examples/network-acls/versions.tf
+++ b/examples/network-acls/versions.tf
@@ -1,5 +1,5 @@
 terraform {
-  required_version = ">= 0.12.7"
+  required_version = ">= 0.12.21"
 
   required_providers {
     aws = ">= 2.68"
diff --git a/examples/secondary-cidr-blocks/README.md b/examples/secondary-cidr-blocks/README.md
index 7305b6767..b41618fef 100644
--- a/examples/secondary-cidr-blocks/README.md
+++ b/examples/secondary-cidr-blocks/README.md
@@ -21,7 +21,7 @@ Note that this example may create resources which can cost money (AWS Elastic IP
 
 | Name | Version |
 |------|---------|
-| terraform | >= 0.12.7 |
+| terraform | >= 0.12.21 |
 | aws | >= 2.68 |
 
 ## Providers
diff --git a/examples/secondary-cidr-blocks/versions.tf b/examples/secondary-cidr-blocks/versions.tf
index 85a2050d0..f52cfcbc8 100644
--- a/examples/secondary-cidr-blocks/versions.tf
+++ b/examples/secondary-cidr-blocks/versions.tf
@@ -1,5 +1,5 @@
 terraform {
-  required_version = ">= 0.12.7"
+  required_version = ">= 0.12.21"
 
   required_providers {
     aws = ">= 2.68"
diff --git a/examples/simple-vpc/README.md b/examples/simple-vpc/README.md
index 8ec386ba9..7bfe5c0b5 100644
--- a/examples/simple-vpc/README.md
+++ b/examples/simple-vpc/README.md
@@ -25,7 +25,7 @@ Note that this example may create resources which can cost money (AWS Elastic IP
 
 | Name | Version |
 |------|---------|
-| terraform | >= 0.12.7 |
+| terraform | >= 0.12.21 |
 | aws | >= 2.68 |
 
 ## Providers
diff --git a/examples/simple-vpc/versions.tf b/examples/simple-vpc/versions.tf
index 85a2050d0..f52cfcbc8 100644
--- a/examples/simple-vpc/versions.tf
+++ b/examples/simple-vpc/versions.tf
@@ -1,5 +1,5 @@
 terraform {
-  required_version = ">= 0.12.7"
+  required_version = ">= 0.12.21"
 
   required_providers {
     aws = ">= 2.68"
diff --git a/examples/vpc-flow-logs/README.md b/examples/vpc-flow-logs/README.md
index 74d8655b4..97d836604 100644
--- a/examples/vpc-flow-logs/README.md
+++ b/examples/vpc-flow-logs/README.md
@@ -23,7 +23,7 @@ Note that this example may create resources which can cost money (AWS Elastic IP
 
 | Name | Version |
 |------|---------|
-| terraform | >= 0.12.7 |
+| terraform | >= 0.12.21 |
 | aws | >= 2.68 |
 | random | >= 2 |
 
diff --git a/examples/vpc-flow-logs/versions.tf b/examples/vpc-flow-logs/versions.tf
index 3d4b1a187..b4b2ca3c4 100644
--- a/examples/vpc-flow-logs/versions.tf
+++ b/examples/vpc-flow-logs/versions.tf
@@ -1,5 +1,5 @@
 terraform {
-  required_version = ">= 0.12.7"
+  required_version = ">= 0.12.21"
 
   required_providers {
     aws    = ">= 2.68"
diff --git a/examples/vpc-separate-private-route-tables/README.md b/examples/vpc-separate-private-route-tables/README.md
index 0d8ef6ede..3f69ceaa0 100644
--- a/examples/vpc-separate-private-route-tables/README.md
+++ b/examples/vpc-separate-private-route-tables/README.md
@@ -21,7 +21,7 @@ Note that this example may create resources which can cost money (AWS Elastic IP
 
 | Name | Version |
 |------|---------|
-| terraform | >= 0.12.7 |
+| terraform | >= 0.12.21 |
 | aws | >= 2.68 |
 
 ## Providers
diff --git a/examples/vpc-separate-private-route-tables/versions.tf b/examples/vpc-separate-private-route-tables/versions.tf
index 85a2050d0..f52cfcbc8 100644
--- a/examples/vpc-separate-private-route-tables/versions.tf
+++ b/examples/vpc-separate-private-route-tables/versions.tf
@@ -1,5 +1,5 @@
 terraform {
-  required_version = ">= 0.12.7"
+  required_version = ">= 0.12.21"
 
   required_providers {
     aws = ">= 2.68"
diff --git a/versions.tf b/versions.tf
index 85a2050d0..f52cfcbc8 100644
--- a/versions.tf
+++ b/versions.tf
@@ -1,5 +1,5 @@
 terraform {
-  required_version = ">= 0.12.7"
+  required_version = ">= 0.12.21"
 
   required_providers {
     aws = ">= 2.68"