diff --git a/.evergreen/config.yml b/.evergreen/config.yml
index 8c4bc4887e..f57ffb1e75 100644
--- a/.evergreen/config.yml
+++ b/.evergreen/config.yml
@@ -1741,10 +1741,6 @@ axes:
         display_name: "4.2"
         variables:
           VERSION: "4.2"
-      - id: "4.0"
-        display_name: "4.0"
-        variables:
-          VERSION: "4.0"
       - id: "rapid"
         display_name: "rapid"
         variables:
@@ -2170,19 +2166,6 @@ buildvariants:
     tasks:
       - name: ".goleak"
 
-  - matrix_name: "tests-rhel-40-with-snappy-support"
-    tags: ["pullrequest"]
-    matrix_spec: { version: ["4.0"], os-ssl-40: ["rhel87-64"] }
-    display_name: "${version} ${os-ssl-40}"
-    tasks:
-      - name: ".test !.enterprise-auth !.zlib !.zstd"
-
-  - matrix_name: "tests-windows-40-with-snappy-support"
-    matrix_spec: { version: ["4.0"], os-ssl-40: ["windows-64"] }
-    display_name: "${version} ${os-ssl-40}"
-    tasks:
-      - name: ".test !.enterprise-auth !.zlib !.zstd"
-
   - matrix_name: "tests-rhel-44-plus-zlib-zstd-support"
     tags: ["pullrequest"]
     matrix_spec: { version: ["4.2", "4.4", "5.0", "6.0", "7.0", "8.0"], os-ssl-40: ["rhel87-64"] }
diff --git a/README.md b/README.md
index 247c7ee5f6..475c5d43d9 100644
--- a/README.md
+++ b/README.md
@@ -24,7 +24,7 @@ The MongoDB Go driver follows [semantic versioning](https://semver.org/) for its
 
 - Go 1.19 or higher. We aim to support the latest versions of Go.
 - Go 1.23 or higher is required to run the driver test suite.
-- MongoDB 4.0 and higher.
+- MongoDB 4.2 and higher.
 
 ## Installation
 
diff --git a/internal/docexamples/examples_test.go b/internal/docexamples/examples_test.go
index 9046971d90..387db97440 100644
--- a/internal/docexamples/examples_test.go
+++ b/internal/docexamples/examples_test.go
@@ -131,14 +131,8 @@ func TestDocumentationExamples(t *testing.T) {
 		docexamples.ChangeStreamExamples(mt.T, csdb)
 	})
 
-	// Causal consistency examples cannot run on 4.0.
-	// TODO(GODRIVER-2238): Remove version filtering once failures on 4.0 sharded clusters are fixed.
-	mtOpts = mtest.NewOptions().MinServerVersion("4.2").Topologies(mtest.ReplicaSet)
-	mt.RunOpts("CausalConsistencyExamples/post4.2", mtOpts, func(mt *mtest.T) {
-		docexamples.CausalConsistencyExamples(mt.Client)
-	})
-	mtOpts = mtest.NewOptions().MaxServerVersion("4.0").Topologies(mtest.ReplicaSet)
-	mt.RunOpts("CausalConsistencyExamples/pre4.0", mtOpts, func(mt *mtest.T) {
+	mtOpts = mtest.NewOptions().Topologies(mtest.ReplicaSet)
+	mt.RunOpts("CausalConsistencyExamples", mtOpts, func(mt *mtest.T) {
 		docexamples.CausalConsistencyExamples(mt.Client)
 	})
 }
diff --git a/internal/driverutil/description.go b/internal/driverutil/description.go
index 899637997f..926de0bdf9 100644
--- a/internal/driverutil/description.go
+++ b/internal/driverutil/description.go
@@ -21,7 +21,7 @@ import (
 )
 
 const (
-	MinWireVersion = 7
+	MinWireVersion = 8
 	MaxWireVersion = 25
 )
 
diff --git a/internal/integration/change_stream_test.go b/internal/integration/change_stream_test.go
index 4bacc746bd..245174a6d0 100644
--- a/internal/integration/change_stream_test.go
+++ b/internal/integration/change_stream_test.go
@@ -259,34 +259,6 @@ func TestChangeStream_ReplicaSet(t *testing.T) {
 		assert.Nil(mt, cs.Err(), "change stream error: %v", cs.Err())
 	})
 
-	startAtOpTimeOpts := mtest.NewOptions().MinServerVersion("4.0").MaxServerVersion("4.0.6")
-	mt.RunOpts("include startAtOperationTime", startAtOpTimeOpts, func(mt *mtest.T) {
-		// $changeStream stage for ChangeStream against a server >=4.0 and <4.0.7 that has not received any results yet
-		// MUST include a startAtOperationTime option when resuming a changestream.
-
-		cs, err := mt.Coll.Watch(context.Background(), mongo.Pipeline{})
-		assert.Nil(mt, err, "Watch error: %v", err)
-		defer closeStream(cs)
-
-		generateEvents(mt, 1)
-		// kill cursor to force resumable error
-		killChangeStreamCursor(mt, cs)
-
-		mt.ClearEvents()
-		// change stream should resume once and get new change
-		assert.True(mt, cs.Next(context.Background()), "expected Next to return true, got false")
-		// Next should cause getMore, killCursors, and aggregate to run
-		assert.NotNil(mt, mt.GetStartedEvent(), "expected getMore event, got nil")
-		assert.NotNil(mt, mt.GetStartedEvent(), "expected killCursors event, got nil")
-		aggEvent := mt.GetStartedEvent()
-		assert.NotNil(mt, aggEvent, "expected aggregate event, got nil")
-		assert.Equal(mt, "aggregate", aggEvent.CommandName, "expected command name 'aggregate', got '%v'", aggEvent.CommandName)
-
-		// check for startAtOperationTime in pipeline
-		csStage := aggEvent.Command.Lookup("pipeline").Array().Index(0).Document() // $changeStream stage
-		_, err = csStage.Lookup("$changeStream").Document().LookupErr("startAtOperationTime")
-		assert.Nil(mt, err, "startAtOperationTime not included in aggregate command")
-	})
 	mt.RunOpts("decode does not panic", noClientOpts, func(mt *mtest.T) {
 		testCases := []struct {
 			name             string
@@ -418,53 +390,6 @@ func TestChangeStream_ReplicaSet(t *testing.T) {
 					})
 				}
 			})
-
-			noPbrtOpts := mtest.NewOptions().MaxServerVersion("4.0.6")
-			mt.RunOpts("without PBRT support", noPbrtOpts, func(mt *mtest.T) {
-				collName := mt.Coll.Name()
-				dbName := mt.Coll.Database().Name()
-				cs, err := mt.Coll.Watch(context.Background(), mongo.Pipeline{})
-				assert.Nil(mt, err, "Watch error: %v", err)
-				defer closeStream(cs)
-
-				compareResumeTokens(mt, cs, nil) // should be no resume token because no PBRT
-				numEvents := 5
-				generateEvents(mt, numEvents)
-				// iterate once to get a resume token
-				assert.True(mt, cs.Next(context.Background()), "expected Next to return true, got false")
-				token := cs.ResumeToken()
-				assert.NotNil(mt, token, "expected resume token, got nil")
-
-				testCases := []struct {
-					name            string
-					opts            *options.ChangeStreamOptionsBuilder
-					iterateStream   bool // whether or not resulting change stream should be iterated
-					initialToken    bson.Raw
-					numDocsExpected int
-				}{
-					{"resumeAfter", options.ChangeStream().SetResumeAfter(token), true, token, numEvents - 1},
-					{"no options", nil, false, nil, 0},
-				}
-				for _, tc := range testCases {
-					mt.Run(tc.name, func(mt *mtest.T) {
-						coll := mt.Client.Database(dbName).Collection(collName)
-						cs, err := coll.Watch(context.Background(), mongo.Pipeline{}, tc.opts)
-						assert.Nil(mt, err, "Watch error: %v", err)
-						defer closeStream(cs)
-
-						compareResumeTokens(mt, cs, tc.initialToken)
-						if !tc.iterateStream {
-							return
-						}
-
-						for i := 0; i < tc.numDocsExpected; i++ {
-							assert.True(mt, cs.Next(context.Background()), "expected Next to return true, got false")
-							// current resume token should always equal _id of current document
-							compareResumeTokens(mt, cs, cs.Current.Lookup("_id").Document())
-						}
-					})
-				}
-			})
 		})
 	})
 	mt.RunOpts("try next", noClientOpts, func(mt *mtest.T) {
@@ -826,17 +751,6 @@ func generateEvents(mt *mtest.T, numEvents int) {
 	}
 }
 
-func killChangeStreamCursor(mt *mtest.T, cs *mongo.ChangeStream) {
-	mt.Helper()
-
-	db := mt.Coll.Database().Client().Database("admin")
-	err := db.RunCommand(context.Background(), bson.D{
-		{"killCursors", mt.Coll.Name()},
-		{"cursors", bson.A{cs.ID()}},
-	}).Err()
-	assert.Nil(mt, err, "killCursors error: %v", err)
-}
-
 // returns pbrt, operationTime from aggregate command response
 func getAggregateResponseInfo(mt *mtest.T) (bson.Raw, bson.Timestamp) {
 	mt.Helper()
diff --git a/internal/integration/primary_stepdown_test.go b/internal/integration/primary_stepdown_test.go
index ac7f7b4f21..0e8bae6a2d 100644
--- a/internal/integration/primary_stepdown_test.go
+++ b/internal/integration/primary_stepdown_test.go
@@ -55,25 +55,16 @@ func TestConnectionsSurvivePrimaryStepDown(t *testing.T) {
 	})
 	mt.RunOpts("server errors", noClientOpts, func(mt *mtest.T) {
 		testCases := []struct {
-			name                   string
-			minVersion, maxVersion string
-			errCode                int32
-			poolCleared            bool
+			name        string
+			errCode     int32
+			poolCleared bool
 		}{
-			{"notPrimary keep pool", "4.2", "", errorNotPrimary, false},
-			{"notPrimary reset pool", "4.0", "4.0", errorNotPrimary, true},
-			{"shutdown in progress reset pool", "4.0", "", errorShutdownInProgress, true},
-			{"interrupted at shutdown reset pool", "4.0", "", errorInterruptedAtShutdown, true},
+			{"notPrimary keep pool", errorNotPrimary, false},
+			{"shutdown in progress reset pool", errorShutdownInProgress, true},
+			{"interrupted at shutdown reset pool", errorInterruptedAtShutdown, true},
 		}
 		for _, tc := range testCases {
-			opts := mtest.NewOptions()
-			if tc.minVersion != "" {
-				opts.MinServerVersion(tc.minVersion)
-			}
-			if tc.maxVersion != "" {
-				opts.MaxServerVersion(tc.maxVersion)
-			}
-			mt.RunOpts(tc.name, opts, func(mt *mtest.T) {
+			mt.Run(tc.name, func(mt *mtest.T) {
 				tpm := eventtest.NewTestPoolMonitor()
 				mt.ResetClient(options.Client().
 					SetRetryWrites(false).
diff --git a/internal/integration/sdam_error_handling_test.go b/internal/integration/sdam_error_handling_test.go
index 9668f52bb6..737cb67830 100644
--- a/internal/integration/sdam_error_handling_test.go
+++ b/internal/integration/sdam_error_handling_test.go
@@ -36,7 +36,6 @@ func TestSDAMErrorHandling(t *testing.T) {
 	baseMtOpts := func() *mtest.Options {
 		mtOpts := mtest.NewOptions().
 			Topologies(mtest.ReplicaSet, mtest.Single). // Don't run on sharded clusters to avoid complexity of sharded failpoints.
-			MinServerVersion("4.0").                    // 4.0+ is required to use failpoints on replica sets.
 			ClientOptions(baseClientOpts())
 
 		if mtest.ClusterTopologyKind() == mtest.Sharded {
@@ -241,7 +240,6 @@ func TestSDAMErrorHandling(t *testing.T) {
 			// This causes the SDAM error handling code path to think we've already handled this state change and
 			// ignore the error because it's stale. To avoid this altogether, we cap the test to <= 4.2.
 			serverErrorsMtOpts := baseMtOpts().
-				MinServerVersion("4.0"). // failCommand support
 				MaxServerVersion("4.2").
 				ClientOptions(baseClientOpts().SetRetryWrites(false))
 
diff --git a/internal/spectest/skip.go b/internal/spectest/skip.go
index 905254ba4a..189b38b447 100644
--- a/internal/spectest/skip.go
+++ b/internal/spectest/skip.go
@@ -841,6 +841,18 @@ var skipTests = map[string][]string{
 	"Support queryable encryption in Client.BulkWrite (GODRIVER-3403)": {
 		"TestUnifiedSpec/crud/tests/unified/client-bulkWrite-qe.json",
 	},
+
+	// Pre-4.2 SDAM tests
+	"Pre-4.2 SDAM tests": {
+		"TestSDAMSpec/errors/pre-42-InterruptedAtShutdown.json",
+		"TestSDAMSpec/errors/pre-42-InterruptedDueToReplStateChange.json",
+		"TestSDAMSpec/errors/pre-42-LegacyNotPrimary.json",
+		"TestSDAMSpec/errors/pre-42-NotPrimaryNoSecondaryOk.json",
+		"TestSDAMSpec/errors/pre-42-NotPrimaryOrSecondary.json",
+		"TestSDAMSpec/errors/pre-42-NotWritablePrimary.json",
+		"TestSDAMSpec/errors/pre-42-PrimarySteppedDown.json",
+		"TestSDAMSpec/errors/pre-42-ShutdownInProgress.json",
+	},
 }
 
 // CheckSkip checks if the fully-qualified test name matches a list of skipped test names for a given reason.
diff --git a/mongo/options/changestreamoptions.go b/mongo/options/changestreamoptions.go
index 9e5bb93b02..92f19638c0 100644
--- a/mongo/options/changestreamoptions.go
+++ b/mongo/options/changestreamoptions.go
@@ -135,7 +135,7 @@ func (cso *ChangeStreamOptionsBuilder) SetShowExpandedEvents(see bool) *ChangeSt
 }
 
 // SetStartAtOperationTime sets the value for the StartAtOperationTime field. If specified, the change stream
-// will only return changes that occurred at or after the given timestamp. This MongoDB versions >= 4.0.
+// will only return changes that occurred at or after the given timestamp.
 // If this is specified, ResumeAfter and StartAfter must not be set.
 func (cso *ChangeStreamOptionsBuilder) SetStartAtOperationTime(t *bson.Timestamp) *ChangeStreamOptionsBuilder {
 	cso.Opts = append(cso.Opts, func(opts *ChangeStreamOptions) error {
diff --git a/mongo/options/listcollectionsoptions.go b/mongo/options/listcollectionsoptions.go
index 14f96cc627..c69a6dc4db 100644
--- a/mongo/options/listcollectionsoptions.go
+++ b/mongo/options/listcollectionsoptions.go
@@ -65,8 +65,7 @@ func (lc *ListCollectionsOptionsBuilder) SetBatchSize(size int32) *ListCollectio
 
 // SetAuthorizedCollections sets the value for the AuthorizedCollections field. If true, and
 // NameOnly is true, limits the documents returned to only contain collections the user is
-// authorized to use. The default value is false. This option is only valid for MongoDB server
-// versions >= 4.0. Server versions < 4.0 ignore this option.
+// authorized to use. The default value is false.
 func (lc *ListCollectionsOptionsBuilder) SetAuthorizedCollections(b bool) *ListCollectionsOptionsBuilder {
 	lc.Opts = append(lc.Opts, func(opts *ListCollectionsOptions) error {
 		opts.AuthorizedCollections = &b
diff --git a/x/mongo/driver/integration/scram_test.go b/x/mongo/driver/integration/scram_test.go
index d75623e051..5638dbfbd9 100644
--- a/x/mongo/driver/integration/scram_test.go
+++ b/x/mongo/driver/integration/scram_test.go
@@ -12,7 +12,6 @@ import (
 	"os"
 	"testing"
 
-	"go.mongodb.org/mongo-driver/v2/internal/driverutil"
 	"go.mongodb.org/mongo-driver/v2/internal/integtest"
 	"go.mongodb.org/mongo-driver/v2/internal/serverselector"
 	"go.mongodb.org/mongo-driver/v2/mongo/options"
@@ -39,10 +38,6 @@ func TestSCRAM(t *testing.T) {
 	noerr(t, err)
 	defer serverConnection.Close()
 
-	if !driverutil.VersionRangeIncludes(*serverConnection.Description().WireVersion, 7) {
-		t.Skip("Skipping because MongoDB 4.0 is needed for SCRAM-SHA-256")
-	}
-
 	// Unicode constants for testing
 	var romanFour = "\u2163" // ROMAN NUMERAL FOUR -> SASL prepped is "IV"
 	var romanNine = "\u2168" // ROMAN NUMERAL NINE -> SASL prepped is "IX"
diff --git a/x/mongo/driver/topology/fsm.go b/x/mongo/driver/topology/fsm.go
index 530b2169e6..26e2fc320b 100644
--- a/x/mongo/driver/topology/fsm.go
+++ b/x/mongo/driver/topology/fsm.go
@@ -20,7 +20,7 @@ import (
 
 var (
 	// MinSupportedMongoDBVersion is the version string for the lowest MongoDB version supported by the driver.
-	MinSupportedMongoDBVersion = "4.0"
+	MinSupportedMongoDBVersion = "4.2"
 
 	// SupportedWireVersions is the range of wire versions supported by the driver.
 	SupportedWireVersions = driverutil.NewVersionRange(driverutil.MinWireVersion, driverutil.MaxWireVersion)
diff --git a/x/mongo/driver/topology/sdam_spec_test.go b/x/mongo/driver/topology/sdam_spec_test.go
index 237e53c33c..eb10d40916 100644
--- a/x/mongo/driver/topology/sdam_spec_test.go
+++ b/x/mongo/driver/topology/sdam_spec_test.go
@@ -463,6 +463,8 @@ func runTest(t *testing.T, directory string, filename string) {
 	assert.Nil(t, err, "ReadFile error: %v", err)
 
 	t.Run(directory+"/"+filename, func(t *testing.T) {
+		spectest.CheckSkip(t)
+
 		var test testCase
 		err = bson.UnmarshalExtJSON(content, false, &test)
 		assert.Nil(t, err, "Unmarshal error: %v", err)
diff --git a/x/mongo/driver/topology/topology_test.go b/x/mongo/driver/topology/topology_test.go
index a4acb4732e..536bb933e8 100644
--- a/x/mongo/driver/topology/topology_test.go
+++ b/x/mongo/driver/topology/topology_test.go
@@ -126,7 +126,7 @@ func TestServerSelection(t *testing.T) {
 		}
 		want := fmt.Errorf(
 			"server at %s reports wire version %d, but this version of the Go driver requires "+
-				"at least 7 (MongoDB 4.0)",
+				"at least 8 (MongoDB 4.2)",
 			desc.Servers[0].Addr.String(),
 			desc.Servers[0].WireVersion.Max,
 		)