diff --git a/README.md b/README.md
index 8268e126c..4a7ee4eea 100644
--- a/README.md
+++ b/README.md
@@ -130,6 +130,7 @@ See [features available for enterprise customers](https://github.com/VictoriaMet
 * [Monitoring](#monitoring)
 * [Troubleshooting](#troubleshooting)
 * [Backfilling](#backfilling)
+* [Data updates](#data-updates)
 * [Replication](#replication)
 * [Backups](#backups)
 * [Profiling](#profiling)
@@ -1077,6 +1078,14 @@ Yet another solution is to increase `-search.cacheTimestampOffset` flag value in
 for data with timestamps close to the current time.
 
 
+### Data updates
+
+VictoriaMetrics doesn't support updating already exiting sample values to new ones. It stores all the ingested data points
+for the same time series with identical timestamps. While is possible substituting old time series with new time series via
+[removal of old time series](#how-to-delete-timeseries) and then [writing new time series](#backfilling), this approach
+should be used only for one-off updates. It shouldn't be used for frequent updates because of non-zero overhead related to data removal.
+
+
 ### Replication
 
 Single-node VictoriaMetrics doesn't support application-level replication. Use cluster version instead.
diff --git a/docs/Single-server-VictoriaMetrics.md b/docs/Single-server-VictoriaMetrics.md
index 8268e126c..4a7ee4eea 100644
--- a/docs/Single-server-VictoriaMetrics.md
+++ b/docs/Single-server-VictoriaMetrics.md
@@ -130,6 +130,7 @@ See [features available for enterprise customers](https://github.com/VictoriaMet
 * [Monitoring](#monitoring)
 * [Troubleshooting](#troubleshooting)
 * [Backfilling](#backfilling)
+* [Data updates](#data-updates)
 * [Replication](#replication)
 * [Backups](#backups)
 * [Profiling](#profiling)
@@ -1077,6 +1078,14 @@ Yet another solution is to increase `-search.cacheTimestampOffset` flag value in
 for data with timestamps close to the current time.
 
 
+### Data updates
+
+VictoriaMetrics doesn't support updating already exiting sample values to new ones. It stores all the ingested data points
+for the same time series with identical timestamps. While is possible substituting old time series with new time series via
+[removal of old time series](#how-to-delete-timeseries) and then [writing new time series](#backfilling), this approach
+should be used only for one-off updates. It shouldn't be used for frequent updates because of non-zero overhead related to data removal.
+
+
 ### Replication
 
 Single-node VictoriaMetrics doesn't support application-level replication. Use cluster version instead.