diff --git a/server/events/runtime/run_step_runner.go b/server/events/runtime/run_step_runner.go
index f7a7cb2fce..1d1f10007a 100644
--- a/server/events/runtime/run_step_runner.go
+++ b/server/events/runtime/run_step_runner.go
@@ -6,13 +6,15 @@ import (
 	"os/exec"
 	"path/filepath"
 
-	version "github.com/hashicorp/go-version"
+	"github.com/hashicorp/go-version"
 	"github.com/runatlantis/atlantis/server/events/models"
 )
 
 // RunStepRunner runs custom commands.
 type RunStepRunner struct {
 	DefaultTFVersion *version.Version
+	// TerraformBinDir is the directory where Atlantis downloads Terraform binaries.
+	TerraformBinDir string
 }
 
 func (r *RunStepRunner) Run(ctx models.ProjectCommandContext, command string, path string) (string, error) {
@@ -32,6 +34,7 @@ func (r *RunStepRunner) Run(ctx models.ProjectCommandContext, command string, pa
 		"HEAD_BRANCH_NAME":           ctx.Pull.HeadBranch,
 		"HEAD_REPO_NAME":             ctx.HeadRepo.Name,
 		"HEAD_REPO_OWNER":            ctx.HeadRepo.Owner,
+		"PATH":                       fmt.Sprintf("%s:%s", os.Getenv("PATH"), r.TerraformBinDir),
 		"PLANFILE":                   filepath.Join(path, GetPlanFilename(ctx.Workspace, ctx.ProjectName)),
 		"PROJECT_NAME":               ctx.ProjectName,
 		"PULL_AUTHOR":                ctx.Pull.Author,
diff --git a/server/events/runtime/run_step_runner_test.go b/server/events/runtime/run_step_runner_test.go
index d12dc7cc8e..f30f250b60 100644
--- a/server/events/runtime/run_step_runner_test.go
+++ b/server/events/runtime/run_step_runner_test.go
@@ -1,10 +1,12 @@
 package runtime_test
 
 import (
+	"fmt"
+	"os"
 	"strings"
 	"testing"
 
-	version "github.com/hashicorp/go-version"
+	"github.com/hashicorp/go-version"
 	"github.com/runatlantis/atlantis/server/events/models"
 	"github.com/runatlantis/atlantis/server/events/runtime"
 	"github.com/runatlantis/atlantis/server/logging"
@@ -62,6 +64,9 @@ func TestRunStepRunner_Run(t *testing.T) {
 		{
 			Command: "echo user_name=$USER_NAME",
 			ExpOut:  "user_name=acme-user\n",
+		}, {
+			Command: "echo $PATH",
+			ExpOut:  fmt.Sprintf("%s:%s\n", os.Getenv("PATH"), "/bin/dir"),
 		},
 	}
 
@@ -70,6 +75,7 @@ func TestRunStepRunner_Run(t *testing.T) {
 	defaultVersion, _ := version.NewVersion("0.8")
 	r := runtime.RunStepRunner{
 		DefaultTFVersion: defaultVersion,
+		TerraformBinDir:  "/bin/dir",
 	}
 	for _, c := range cases {
 		t.Run(c.Command, func(t *testing.T) {
diff --git a/server/events/terraform/terraform_client.go b/server/events/terraform/terraform_client.go
index a42d7bd825..332768e563 100644
--- a/server/events/terraform/terraform_client.go
+++ b/server/events/terraform/terraform_client.go
@@ -27,9 +27,9 @@ import (
 	"strings"
 	"sync"
 
-	getter "github.com/hashicorp/go-getter"
-	version "github.com/hashicorp/go-version"
-	homedir "github.com/mitchellh/go-homedir"
+	"github.com/hashicorp/go-getter"
+	"github.com/hashicorp/go-version"
+	"github.com/mitchellh/go-homedir"
 	"github.com/pkg/errors"
 	"github.com/runatlantis/atlantis/server/logging"
 )
@@ -177,6 +177,11 @@ func (c *DefaultClient) DefaultVersion() *version.Version {
 	return c.defaultVersion
 }
 
+// TerraformBinDir returns the directory where we download Terraform binaries.
+func (c *DefaultClient) TerraformBinDir() string {
+	return c.binDir
+}
+
 // See Client.RunCommandWithVersion.
 func (c *DefaultClient) RunCommandWithVersion(log *logging.SimpleLogger, path string, args []string, v *version.Version, workspace string) (string, error) {
 	tfCmd, cmd, err := c.prepCmd(log, v, workspace, path, args)
diff --git a/server/server.go b/server/server.go
index 5289c58957..eaa29f13b9 100644
--- a/server/server.go
+++ b/server/server.go
@@ -283,6 +283,7 @@ func NewServer(userConfig UserConfig, config Config) (*Server, error) {
 			},
 			RunStepRunner: &runtime.RunStepRunner{
 				DefaultTFVersion: defaultTfVersion,
+				TerraformBinDir:  terraformClient.TerraformBinDir(),
 			},
 			PullApprovedChecker: vcsClient,
 			WorkingDir:          workingDir,