diff --git a/pgconn.go b/pgconn.go
index 223b8e3d..db741d47 100644
--- a/pgconn.go
+++ b/pgconn.go
@@ -504,6 +504,7 @@ func (pgConn *PgConn) Prepare(ctx context.Context, name, sql string, paramOIDs [
 
 	select {
 	case <-ctx.Done():
+		pgConn.unlock()
 		return nil, ctx.Err()
 	default:
 	}
@@ -626,6 +627,7 @@ func (pgConn *PgConn) WaitForNotification(ctx context.Context) error {
 
 	select {
 	case <-ctx.Done():
+		pgConn.unlock()
 		return ctx.Err()
 	default:
 	}
@@ -668,6 +670,7 @@ func (pgConn *PgConn) Exec(ctx context.Context, sql string) *MultiResultReader {
 	case <-ctx.Done():
 		multiResult.closed = true
 		multiResult.err = ctx.Err()
+		pgConn.unlock()
 		return multiResult
 	default:
 	}
@@ -828,6 +831,7 @@ func (pgConn *PgConn) CopyTo(ctx context.Context, w io.Writer, sql string) (Comm
 
 	select {
 	case <-ctx.Done():
+		pgConn.unlock()
 		return "", ctx.Err()
 	default:
 	}
@@ -1278,6 +1282,7 @@ func (pgConn *PgConn) ExecBatch(ctx context.Context, batch *Batch) *MultiResultR
 	case <-ctx.Done():
 		multiResult.closed = true
 		multiResult.err = ctx.Err()
+		pgConn.unlock()
 		return multiResult
 	default:
 	}
diff --git a/pgconn_test.go b/pgconn_test.go
index b2514e48..66a4337b 100644
--- a/pgconn_test.go
+++ b/pgconn_test.go
@@ -255,6 +255,23 @@ func TestConnPrepareSyntaxError(t *testing.T) {
 	ensureConnValid(t, pgConn)
 }
 
+func TestConnPrepareContextPrecanceled(t *testing.T) {
+	t.Parallel()
+
+	pgConn, err := pgconn.Connect(context.Background(), os.Getenv("PGX_TEST_DATABASE"))
+	require.NoError(t, err)
+	defer closeConn(t, pgConn)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+	psd, err := pgConn.Prepare(ctx, "ps1", "select 1", nil)
+	require.Nil(t, psd)
+	require.Error(t, err)
+	require.Equal(t, context.Canceled, err)
+
+	ensureConnValid(t, pgConn)
+}
+
 func TestConnExec(t *testing.T) {
 	t.Parallel()
 
@@ -360,6 +377,22 @@ func TestConnExecContextCanceled(t *testing.T) {
 	assert.False(t, pgConn.IsAlive())
 }
 
+func TestConnExecContextPrecanceled(t *testing.T) {
+	t.Parallel()
+
+	pgConn, err := pgconn.Connect(context.Background(), os.Getenv("PGX_TEST_DATABASE"))
+	require.NoError(t, err)
+	defer closeConn(t, pgConn)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+	_, err = pgConn.Exec(ctx, "select 'Hello, world'").ReadAll()
+	require.Error(t, err)
+	require.Equal(t, context.Canceled, err)
+
+	ensureConnValid(t, pgConn)
+}
+
 func TestConnExecParams(t *testing.T) {
 	t.Parallel()
 
@@ -449,6 +482,22 @@ func TestConnExecParamsCanceled(t *testing.T) {
 	assert.False(t, pgConn.IsAlive())
 }
 
+func TestConnExecParamsPrecanceled(t *testing.T) {
+	t.Parallel()
+
+	pgConn, err := pgconn.Connect(context.Background(), os.Getenv("PGX_TEST_DATABASE"))
+	require.NoError(t, err)
+	defer closeConn(t, pgConn)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+	result := pgConn.ExecParams(ctx, "select $1::text", [][]byte{[]byte("Hello, world")}, nil, nil, nil).Read()
+	require.Error(t, result.Err)
+	require.Equal(t, context.Canceled, result.Err)
+
+	ensureConnValid(t, pgConn)
+}
+
 func TestConnExecPrepared(t *testing.T) {
 	t.Parallel()
 
@@ -558,6 +607,25 @@ func TestConnExecPreparedCanceled(t *testing.T) {
 	assert.False(t, pgConn.IsAlive())
 }
 
+func TestConnExecPreparedPrecanceled(t *testing.T) {
+	t.Parallel()
+
+	pgConn, err := pgconn.Connect(context.Background(), os.Getenv("PGX_TEST_DATABASE"))
+	require.NoError(t, err)
+	defer closeConn(t, pgConn)
+
+	_, err = pgConn.Prepare(context.Background(), "ps1", "select current_database(), pg_sleep(1)", nil)
+	require.NoError(t, err)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+	result := pgConn.ExecPrepared(ctx, "ps1", nil, nil, nil).Read()
+	require.Error(t, result.Err)
+	require.Equal(t, context.Canceled, result.Err)
+
+	ensureConnValid(t, pgConn)
+}
+
 func TestConnExecBatch(t *testing.T) {
 	t.Parallel()
 
@@ -590,6 +658,31 @@ func TestConnExecBatch(t *testing.T) {
 	assert.Equal(t, "SELECT 1", string(results[2].CommandTag))
 }
 
+func TestConnExecBatchPrecanceled(t *testing.T) {
+	t.Parallel()
+
+	pgConn, err := pgconn.Connect(context.Background(), os.Getenv("PGX_TEST_DATABASE"))
+	require.NoError(t, err)
+	defer closeConn(t, pgConn)
+
+	_, err = pgConn.Prepare(context.Background(), "ps1", "select $1::text", nil)
+	require.NoError(t, err)
+
+	batch := &pgconn.Batch{}
+
+	batch.ExecParams("select $1::text", [][]byte{[]byte("ExecParams 1")}, nil, nil, nil)
+	batch.ExecPrepared("ps1", [][]byte{[]byte("ExecPrepared 1")}, nil, nil)
+	batch.ExecParams("select $1::text", [][]byte{[]byte("ExecParams 2")}, nil, nil, nil)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+	_, err = pgConn.ExecBatch(ctx, batch).ReadAll()
+	require.Error(t, err)
+	require.Equal(t, context.Canceled, err)
+
+	ensureConnValid(t, pgConn)
+}
+
 func TestConnLocking(t *testing.T) {
 	t.Parallel()
 
@@ -726,6 +819,24 @@ func TestConnWaitForNotification(t *testing.T) {
 	ensureConnValid(t, pgConn)
 }
 
+func TestConnWaitForNotificationPrecanceled(t *testing.T) {
+	t.Parallel()
+
+	config, err := pgconn.ParseConfig(os.Getenv("PGX_TEST_DATABASE"))
+	require.NoError(t, err)
+
+	pgConn, err := pgconn.ConnectConfig(context.Background(), config)
+	require.NoError(t, err)
+	defer closeConn(t, pgConn)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+	err = pgConn.WaitForNotification(ctx)
+	require.Equal(t, context.Canceled, err)
+
+	ensureConnValid(t, pgConn)
+}
+
 func TestConnWaitForNotificationTimeout(t *testing.T) {
 	t.Parallel()
 
@@ -855,6 +966,25 @@ func TestConnCopyToCanceled(t *testing.T) {
 	assert.False(t, pgConn.IsAlive())
 }
 
+func TestConnCopyToPrecanceled(t *testing.T) {
+	t.Parallel()
+
+	pgConn, err := pgconn.Connect(context.Background(), os.Getenv("PGX_TEST_DATABASE"))
+	require.NoError(t, err)
+	defer closeConn(t, pgConn)
+
+	outputWriter := &bytes.Buffer{}
+
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+	res, err := pgConn.CopyTo(ctx, outputWriter, "copy (select * from generate_series(1,1000)) to stdout")
+	require.Error(t, err)
+	require.Equal(t, context.Canceled, err)
+	assert.Equal(t, pgconn.CommandTag(""), res)
+
+	ensureConnValid(t, pgConn)
+}
+
 func TestConnCopyFrom(t *testing.T) {
 	t.Parallel()
 
@@ -926,6 +1056,42 @@ func TestConnCopyFromCanceled(t *testing.T) {
 	assert.False(t, pgConn.IsAlive())
 }
 
+func TestConnCopyFromPrecanceled(t *testing.T) {
+	t.Parallel()
+
+	pgConn, err := pgconn.Connect(context.Background(), os.Getenv("PGX_TEST_DATABASE"))
+	require.NoError(t, err)
+	defer closeConn(t, pgConn)
+
+	_, err = pgConn.Exec(context.Background(), `create temporary table foo(
+		a int4,
+		b varchar
+	)`).ReadAll()
+	require.NoError(t, err)
+
+	r, w := io.Pipe()
+	go func() {
+		for i := 0; i < 1000000; i++ {
+			a := strconv.Itoa(i)
+			b := "foo " + a + " bar"
+			_, err := w.Write([]byte(fmt.Sprintf("%s,\"%s\"\n", a, b)))
+			if err != nil {
+				return
+			}
+			time.Sleep(time.Microsecond)
+		}
+	}()
+
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+	ct, err := pgConn.CopyFrom(ctx, r, "COPY foo FROM STDIN WITH (FORMAT csv)")
+	require.Error(t, err)
+	require.Equal(t, context.Canceled, err)
+	assert.Equal(t, pgconn.CommandTag(""), ct)
+
+	ensureConnValid(t, pgConn)
+}
+
 func TestConnCopyFromGzipReader(t *testing.T) {
 	t.Parallel()