diff --git a/storage/errors.go b/storage/errors.go
new file mode 100644
index 000000000..eff70f678
--- /dev/null
+++ b/storage/errors.go
@@ -0,0 +1,48 @@
+// Copyright 2014 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package storage
+
+import "fmt"
+
+type errDuplicateSampleForTimestamp struct {
+	timestamp int64
+	existing  float64
+	newValue  float64
+}
+
+func NewDuplicateFloatErr(t int64, existing, newValue float64) error {
+	return errDuplicateSampleForTimestamp{
+		timestamp: t,
+		existing:  existing,
+		newValue:  newValue,
+	}
+}
+
+func (e errDuplicateSampleForTimestamp) Error() string {
+	if e.timestamp == 0 {
+		return "duplicate sample for timestamp"
+	}
+	return fmt.Sprintf("duplicate sample for timestamp %d; overrides not allowed: existing %g, new value %g", e.timestamp, e.existing, e.newValue)
+}
+
+// Every errDuplicateSampleForTimestamp compares equal to the global ErrDuplicateSampleForTimestamp.
+func (e errDuplicateSampleForTimestamp) Is(t error) bool {
+	if t == ErrDuplicateSampleForTimestamp {
+		return true
+	}
+	if v, ok := t.(errDuplicateSampleForTimestamp); ok {
+		return e == v
+	}
+	return false
+}
diff --git a/storage/interface.go b/storage/interface.go
index 347e779b5..493c2d689 100644
--- a/storage/interface.go
+++ b/storage/interface.go
@@ -37,7 +37,7 @@ var (
 	// ErrTooOldSample is when out of order support is enabled but the sample is outside the time window allowed.
 	ErrTooOldSample = errors.New("too old sample")
 	// ErrDuplicateSampleForTimestamp is when the sample has same timestamp but different value.
-	ErrDuplicateSampleForTimestamp = errors.New("duplicate sample for timestamp")
+	ErrDuplicateSampleForTimestamp = errDuplicateSampleForTimestamp{}
 	ErrOutOfOrderExemplar          = errors.New("out of order exemplar")
 	ErrDuplicateExemplar           = errors.New("duplicate exemplar")
 	ErrExemplarLabelLength         = fmt.Errorf("label length for exemplar exceeds maximum of %d UTF-8 characters", exemplar.ExemplarMaxLabelSetLength)
diff --git a/tsdb/db_test.go b/tsdb/db_test.go
index 5965e5317..f0d672fad 100644
--- a/tsdb/db_test.go
+++ b/tsdb/db_test.go
@@ -503,7 +503,7 @@ func TestAmendHistogramDatapointCausesError(t *testing.T) {
 	_, err = app.Append(0, labels.FromStrings("a", "b"), 0, 0)
 	require.NoError(t, err)
 	_, err = app.Append(0, labels.FromStrings("a", "b"), 0, 1)
-	require.Equal(t, storage.ErrDuplicateSampleForTimestamp, err)
+	require.ErrorIs(t, err, storage.ErrDuplicateSampleForTimestamp)
 	require.NoError(t, app.Rollback())
 
 	h := histogram.Histogram{
@@ -579,7 +579,7 @@ func TestNonDuplicateNaNDatapointsCausesAmendError(t *testing.T) {
 
 	app = db.Appender(ctx)
 	_, err = app.Append(0, labels.FromStrings("a", "b"), 0, math.Float64frombits(0x7ff0000000000002))
-	require.Equal(t, storage.ErrDuplicateSampleForTimestamp, err)
+	require.ErrorIs(t, err, storage.ErrDuplicateSampleForTimestamp)
 }
 
 func TestEmptyLabelsetCausesError(t *testing.T) {
diff --git a/tsdb/head_append.go b/tsdb/head_append.go
index 224f65314..62c3727e2 100644
--- a/tsdb/head_append.go
+++ b/tsdb/head_append.go
@@ -467,7 +467,7 @@ func (s *memSeries) appendable(t int64, v float64, headMaxt, minValidTime, oooTi
 			// This only checks against the latest in-order sample.
 			// The OOO headchunk has its own method to detect these duplicates.
 			if math.Float64bits(s.lastValue) != math.Float64bits(v) {
-				return false, 0, storage.ErrDuplicateSampleForTimestamp
+				return false, 0, storage.NewDuplicateFloatErr(t, s.lastValue, v)
 			}
 			// Sample is identical (ts + value) with most current (highest ts) sample in sampleBuf.
 			return false, 0, nil