diff --git a/id.go b/id.go
index 5bf262ab9d..307a6870f3 100644
--- a/id.go
+++ b/id.go
@@ -3,7 +3,6 @@ package influxdb
 import (
 	"encoding/binary"
 	"encoding/hex"
-	"encoding/json"
 	"errors"
 	"reflect"
 	"strconv"
@@ -119,24 +118,17 @@ func (i ID) GoString() string {
 	return `"` + i.String() + `"`
 }
 
-// UnmarshalJSON implements JSON unmarshaller for IDs.
-func (i *ID) UnmarshalJSON(b []byte) error {
-	if b[0] == '"' {
-		b = b[1:]
-	}
-
-	if b[len(b)-1] == '"' {
-		b = b[:len(b)-1]
-	}
+// MarshalText encodes i as text.
+// Providing this method is a fallback for json.Marshal,
+// with the added benefit that IDs encoded as map keys will be the expected string encoding,
+// rather than the effective fmt.Sprintf("%d", i) that json.Marshal uses by default for integer types.
+func (i ID) MarshalText() ([]byte, error) {
+	return i.Encode()
+}
 
+// UnmarshalText decodes i from a byte slice.
+// Providing this method is also a fallback for json.Unmarshal,
+// also relevant when IDs are used as map keys.
+func (i *ID) UnmarshalText(b []byte) error {
 	return i.Decode(b)
 }
-
-// MarshalJSON implements JSON marshaller for IDs.
-func (i ID) MarshalJSON() ([]byte, error) {
-	enc, err := i.Encode()
-	if err != nil {
-		return nil, err
-	}
-	return json.Marshal(string(enc))
-}
diff --git a/id_test.go b/id_test.go
index 13bf7ce173..58f25ff6d5 100644
--- a/id_test.go
+++ b/id_test.go
@@ -7,6 +7,7 @@ import (
 	"reflect"
 	"testing"
 
+	"github.com/influxdata/influxdb"
 	platform "github.com/influxdata/influxdb"
 	platformtesting "github.com/influxdata/influxdb/testing"
 )
@@ -181,6 +182,28 @@ func TestMarshalling(t *testing.T) {
 	if !bytes.Equal(bytes1, bytes2) {
 		t.Errorf("error marshalling/unmarshalling ID")
 	}
+
+	// When used as a map key, IDs must use their string encoding.
+	// If you only implement json.Marshaller, they will be encoded with Go's default integer encoding.
+	b, err := json.Marshal(map[influxdb.ID]int{0x1234: 5678})
+	if err != nil {
+		t.Error(err)
+	}
+	const exp = `{"0000000000001234":5678}`
+	if string(b) != exp {
+		t.Errorf("expected map to json.Marshal as %s; got %s", exp, string(b))
+	}
+
+	var idMap map[influxdb.ID]int
+	if err := json.Unmarshal(b, &idMap); err != nil {
+		t.Error(err)
+	}
+	if len(idMap) != 1 {
+		t.Errorf("expected length 1, got %d", len(idMap))
+	}
+	if idMap[0x1234] != 5678 {
+		t.Errorf("unmarshalled incorrectly; exp 0x1234:5678, got %v", idMap)
+	}
 }
 
 func TestValid(t *testing.T) {
diff --git a/source.go b/source.go
index e64189ff3d..c62ded99ce 100644
--- a/source.go
+++ b/source.go
@@ -23,7 +23,7 @@ const (
 // TODO(desa): do we still need default?
 // TODO(desa): do sources belong
 type Source struct {
-	ID                 ID         `json:"id,string,omitempty"`          // ID is the unique ID of the source
+	ID                 ID         `json:"id,omitempty"`                 // ID is the unique ID of the source
 	OrganizationID     ID         `json:"orgID"`                        // OrganizationID is the organization ID that resource belongs to
 	Default            bool       `json:"default"`                      // Default specifies the default source for the application
 	Name               string     `json:"name"`                         // Name is the user-defined name for the source