diff --git a/bin/import-sql b/bin/import-sql
index 215727fc..c2af86dc 100755
--- a/bin/import-sql
+++ b/bin/import-sql
@@ -4,6 +4,16 @@ set -o pipefail
 set -o nounset
 shopt -s nullglob
 
+# For backward compatibility, allow both PG* and POSTGRES_* forms,
+# with the non-standard POSTGRES_* form taking precedence.
+# An error will be raised if neither form is given, except for the PGPORT
+export PGHOST="${POSTGRES_HOST:-${PGHOST?}}"
+export PGDATABASE="${POSTGRES_DB:-${PGDATABASE?}}"
+export PGUSER="${POSTGRES_USER:-${PGUSER?}}"
+export PGPASSWORD="${POSTGRES_PASSWORD:-${PGPASSWORD?}}"
+export PGPORT="${POSTGRES_PORT:-${PGPORT:-5432}}"
+
+
 function exec_psql_file() {
     local file_name="$1"
     # Allws additional parameters to be passed to psql
@@ -14,12 +24,8 @@ function exec_psql_file() {
     echo "Importing $file_name (md5 $(md5sum < "$file_name")  $(wc -l < "$file_name") lines) into Postgres..."
 
     # shellcheck disable=SC2154
-    PGPASSWORD="$POSTGRES_PASSWORD" psql \
+    psql \
         -v ON_ERROR_STOP="1" \
-        --host="$POSTGRES_HOST" \
-        ${POSTGRES_PORT:+ --port="$POSTGRES_PORT"} \
-        --dbname="$POSTGRES_DB" \
-        --username="$POSTGRES_USER" \
         -c '\timing on' \
         -f "$file_name" \
         "${psql_opts[@]}"
diff --git a/docker/generate-vectortiles/README.md b/docker/generate-vectortiles/README.md
index 37a7d2b3..29ad4c8f 100644
--- a/docker/generate-vectortiles/README.md
+++ b/docker/generate-vectortiles/README.md
@@ -12,10 +12,15 @@ You need to provide the database credentials and run `generate-vectortiles`.
 docker run --rm \
     -v $(pwd)/project.tm2source:/tm2source \
     -v $(pwd):/export \
-    -e POSTGRES_USER="osm" \
-    -e POSTGRES_PASSWORD="osm" \
-    -e POSTGRES_HOST="127.0.0.1" \
-    -e POSTGRES_DB="osm" \
-    -e POSTGRES_PORT="5432" \
+    -e PGHOST="127.0.0.1" \
+    -e PGDATABASE="openmaptiles" \
+    -e PGUSER="openmaptiles" \
+    -e PGPASSWORD="openmaptiles" \
     openmaptiles/generate-vectortiles
 ```
+
+Optional environment variables:
+* `PGPORT` (defaults to `5432`)
+
+Legacy env variables are still supported, but they are not recommended:
+`POSTGRES_HOST`,`POSTGRES_DB`, `POSTGRES_USER`, `POSTGRES_PASSWORD`, `POSTGRES_PORT`
diff --git a/docker/generate-vectortiles/utils.sh b/docker/generate-vectortiles/utils.sh
index 791a4aba..0aa306ef 100755
--- a/docker/generate-vectortiles/utils.sh
+++ b/docker/generate-vectortiles/utils.sh
@@ -5,6 +5,15 @@ set -o pipefail
 readonly DEST_PROJECT_DIR="/tmp/project"
 readonly DEST_PROJECT_FILE="${DEST_PROJECT_DIR%%/}/data.yml"
 
+# For backward compatibility, allow both PG* and POSTGRES_* forms,
+# with the non-standard POSTGRES_* form taking precedence.
+# An error will be raised if neither form is given, except for the PGPORT
+PGHOST="${POSTGRES_HOST:-${PGHOST?}}"
+PGDATABASE="${POSTGRES_DB:-${PGDATABASE?}}"
+PGUSER="${POSTGRES_USER:-${PGUSER?}}"
+PGPASSWORD="${POSTGRES_PASSWORD:-${PGPASSWORD?}}"
+PGPORT="${POSTGRES_PORT:-${PGPORT:-5432}}"
+
 # project config will be copied to new folder because we
 # modify the source configuration
 function copy_source_project() {
@@ -19,11 +28,11 @@ function cleanup_dest_project() {
 
 # replace database connection with postgis container connection
 function replace_db_connection() {
-    local replace_expr_1="s|host: .*|host: \"$POSTGRES_HOST\"|g"
-    local replace_expr_2="s|port: .*|port: \"$POSTGRES_PORT\"|g"
-    local replace_expr_3="s|dbname: .*|dbname: \"$POSTGRES_DB\"|g"
-    local replace_expr_4="s|user: .*|user: \"$POSTGRES_USER\"|g"
-    local replace_expr_5="s|password: .*|password: \"$POSTGRES_PASSWORD\"|g"
+    local replace_expr_1="s|host: .*|host: \"$PGHOST\"|g"
+    local replace_expr_2="s|port: .*|port: \"$PGPORT\"|g"
+    local replace_expr_3="s|dbname: .*|dbname: \"$PGDATABASE\"|g"
+    local replace_expr_4="s|user: .*|user: \"$PGUSER\"|g"
+    local replace_expr_5="s|password: .*|password: \"$PGPASSWORD\"|g"
 
     sed -i "$replace_expr_1" "$DEST_PROJECT_FILE"
     sed -i "$replace_expr_2" "$DEST_PROJECT_FILE"
diff --git a/docker/import-sql/README.md b/docker/import-sql/README.md
index d6fe1de1..27e1ef09 100644
--- a/docker/import-sql/README.md
+++ b/docker/import-sql/README.md
@@ -1,6 +1,6 @@
 # !! OBSOLETE !!
 
-This image is obsolete, and should not be used. Use `openmaptiles-tools` image instead. `import_sql.sh` was copied to `/bin`.
+This image is obsolete, and should not be used. Use `openmaptiles-tools` image instead. `import_sql.sh` was copied to `/bin` and should be used as `import-sql` command.
 
 ## Import SQL files into PostgreSQL [![Docker Automated buil](https://img.shields.io/docker/automated/openmaptiles/import-sql.svg)](https://hub.docker.com/r/openmaptiles/import-sql/)