diff --git a/Dockerfile b/Dockerfile
index 7b772cb..3e40fbc 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -3,7 +3,7 @@ FROM alpine:3
 WORKDIR /root
 
 RUN apk update && \
-    apk add bash curl pigz postgresql13-client postgresql14-client postgresql15-client postgresql16-client rclone
+    apk add bash curl pigz postgresql14-client postgresql15-client postgresql16-client rclone
 
 COPY docker-entrypoint.sh /usr/local/bin/
 RUN chmod +x /usr/local/bin/docker-entrypoint.sh
diff --git a/README.md b/README.md
index b474f94..9f821df 100644
--- a/README.md
+++ b/README.md
@@ -20,7 +20,7 @@
 | POSTGRES_PASSWORD      |    ✔     |               | Postgres server password                                                                                                      |
 | POSTGRES_PORT          |          | 5432          | Postgres server port                                                                                                          |
 | POSTGRES_USER          |          | postgres      | Postgres server user                                                                                                          |
-| POSTGRES_VERSION       |          | 16            | Postgres server version (13, 14, 15 or 16)                                                                                    |
+| POSTGRES_VERSION       |          | 16            | Postgres server version (14, 15 or 16)                                                                                        |
 | WEBGAZER_HEARTBEAT_URL |          |               | [WebGazer Heartbeat Monitor](https://www.webgazer.io/services/cron-job-monitoring) URL                                        |
 
 ### Running
diff --git a/docker-entrypoint.sh b/docker-entrypoint.sh
index 3e190aa..0622113 100644
--- a/docker-entrypoint.sh
+++ b/docker-entrypoint.sh
@@ -20,7 +20,7 @@ POSTGRES_USER="${POSTGRES_USER:-postgres}"
 POSTGRES_VERSION="${POSTGRES_VERSION:-16}"
 
 # validate environment variables
-POSTGRES_VERSIONS=(13 14 15 16)
+POSTGRES_VERSIONS=(14 15 16)
 
 if [[ ! " ${POSTGRES_VERSIONS[*]} " =~ " ${POSTGRES_VERSION} " ]]; then
   echo "error: POSTGRES_VERSION can be one of these: ${POSTGRES_VERSIONS[*]}"