diff --git a/CHANGELOG.md b/CHANGELOG.md
index 09c55f9..ff60c38 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -9,6 +9,7 @@
 ### Added
 
 - integrated support for TreeTagger (`-T treetagger`) and spaCy (`-T spacy`) annotations
+- automatically gzip output for now, w2v, conllu target formats if output file (`-o` option) ends with `.gz`
 
 ## [v3.0.0] - 2025-11-27
 
diff --git a/app/src/main/kotlin/de/ids_mannheim/korapxmltools/KorapXmlTool.kt b/app/src/main/kotlin/de/ids_mannheim/korapxmltools/KorapXmlTool.kt
index d9113b1..15aaf2b 100644
--- a/app/src/main/kotlin/de/ids_mannheim/korapxmltools/KorapXmlTool.kt
+++ b/app/src/main/kotlin/de/ids_mannheim/korapxmltools/KorapXmlTool.kt
@@ -840,6 +840,14 @@
             }
             // Create parent directories
             file.parentFile?.mkdirs()
+            
+            // Initialize output writer with optional gzip compression
+            val outputStream = FileOutputStream(file)
+            textOutputWriter = if (finalOutputPath.endsWith(".gz")) {
+                BufferedWriter(OutputStreamWriter(GZIPOutputStream(outputStream), StandardCharsets.UTF_8))
+            } else {
+                BufferedWriter(OutputStreamWriter(outputStream, StandardCharsets.UTF_8))
+            }
         }
 
         LOGGER.info("Processing zip files: " + zipFileNames!!.joinToString(", "))
@@ -1012,6 +1020,7 @@
     var krillTarOutputStream: TarArchiveOutputStream? = null
     var krillOutputFileName: String? = null
     private var krillOutputPath: String? = null
+    private var textOutputWriter: BufferedWriter? = null
 
     // Fast DocumentBuilderFactory without security features (safe for trusted input)
     private val fastDomFactory: DocumentBuilderFactory by lazy {
@@ -1468,6 +1477,10 @@
             // No external worker: ensure progress bar is closed (e.g., internal tagger -t)
             progressBar?.close()
         }
+        
+        // Close text output writer if it was used
+        textOutputWriter?.close()
+        
         // Shutdown entry executor
         entryExecutor?.shutdown()