diff --git a/bramble-core/src/main/java/org/briarproject/bramble/db/Migration38_39.java b/bramble-core/src/main/java/org/briarproject/bramble/db/Migration38_39.java
index 089fd6308..24bc7b33c 100644
--- a/bramble-core/src/main/java/org/briarproject/bramble/db/Migration38_39.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/db/Migration38_39.java
@@ -37,6 +37,7 @@ class Migration38_39 implements Migration<Connection> {
 			s.execute("ALTER TABLE incomingKeys"
 					+ " ALTER COLUMN contactId"
 					+ " SET NOT NULL");
+			s.close();
 		} catch (SQLException e) {
 			tryToClose(s, LOG, WARNING);
 			throw new DbException(e);
diff --git a/bramble-core/src/main/java/org/briarproject/bramble/db/Migration39_40.java b/bramble-core/src/main/java/org/briarproject/bramble/db/Migration39_40.java
index 882775f90..b7d29b206 100644
--- a/bramble-core/src/main/java/org/briarproject/bramble/db/Migration39_40.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/db/Migration39_40.java
@@ -36,6 +36,7 @@ class Migration39_40 implements Migration<Connection> {
 			s.execute("ALTER TABLE statuses"
 					+ " ALTER COLUMN eta"
 					+ " SET NOT NULL");
+			s.close();
 		} catch (SQLException e) {
 			tryToClose(s, LOG, WARNING);
 			throw new DbException(e);
diff --git a/bramble-core/src/main/java/org/briarproject/bramble/db/Migration40_41.java b/bramble-core/src/main/java/org/briarproject/bramble/db/Migration40_41.java
index 8c7f9bcf6..b837f90ef 100644
--- a/bramble-core/src/main/java/org/briarproject/bramble/db/Migration40_41.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/db/Migration40_41.java
@@ -38,6 +38,7 @@ class Migration40_41 implements Migration<Connection> {
 			s = txn.createStatement();
 			s.execute("ALTER TABLE contacts"
 					+ dbTypes.replaceTypes(" ADD alias _STRING"));
+			s.close();
 		} catch (SQLException e) {
 			tryToClose(s, LOG, WARNING);
 			throw new DbException(e);
diff --git a/bramble-core/src/main/java/org/briarproject/bramble/db/Migration41_42.java b/bramble-core/src/main/java/org/briarproject/bramble/db/Migration41_42.java
index 9a9f01633..119cf7c49 100644
--- a/bramble-core/src/main/java/org/briarproject/bramble/db/Migration41_42.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/db/Migration41_42.java
@@ -89,6 +89,7 @@ class Migration41_42 implements Migration<Connection> {
 					+ " FOREIGN KEY (keySetId)"
 					+ " REFERENCES outgoingHandshakeKeys (keySetId)"
 					+ " ON DELETE CASCADE)"));
+			s.close();
 		} catch (SQLException e) {
 			tryToClose(s, LOG, WARNING);
 			throw new DbException(e);
diff --git a/bramble-core/src/main/java/org/briarproject/bramble/db/Migration42_43.java b/bramble-core/src/main/java/org/briarproject/bramble/db/Migration42_43.java
index 809c48589..5946eecf1 100644
--- a/bramble-core/src/main/java/org/briarproject/bramble/db/Migration42_43.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/db/Migration42_43.java
@@ -44,6 +44,7 @@ class Migration42_43 implements Migration<Connection> {
 					+ " ADD COLUMN handshakePublicKey _BINARY"));
 			s.execute("ALTER TABLE contacts"
 					+ " DROP COLUMN active");
+			s.close();
 		} catch (SQLException e) {
 			tryToClose(s, LOG, WARNING);
 			throw new DbException(e);
diff --git a/bramble-core/src/main/java/org/briarproject/bramble/db/Migration43_44.java b/bramble-core/src/main/java/org/briarproject/bramble/db/Migration43_44.java
index 530cbe0e9..39f331e2f 100644
--- a/bramble-core/src/main/java/org/briarproject/bramble/db/Migration43_44.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/db/Migration43_44.java
@@ -50,6 +50,7 @@ class Migration43_44 implements Migration<Connection> {
 					+ " ADD COLUMN rootKey _SECRET"));
 			s.execute("ALTER TABLE outgoingKeys"
 					+ " ADD COLUMN alice BOOLEAN");
+			s.close();
 		} catch (SQLException e) {
 			tryToClose(s, LOG, WARNING);
 			throw new DbException(e);
diff --git a/bramble-core/src/main/java/org/briarproject/bramble/db/Migration44_45.java b/bramble-core/src/main/java/org/briarproject/bramble/db/Migration44_45.java
index 62ce1cb0f..7f898403a 100644
--- a/bramble-core/src/main/java/org/briarproject/bramble/db/Migration44_45.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/db/Migration44_45.java
@@ -31,6 +31,7 @@ class Migration44_45 implements Migration<Connection> {
 		try {
 			s = txn.createStatement();
 			s.execute("ALTER TABLE pendingContacts DROP COLUMN state");
+			s.close();
 		} catch (SQLException e) {
 			tryToClose(s, LOG, WARNING);
 			throw new DbException(e);
diff --git a/bramble-core/src/main/java/org/briarproject/bramble/db/Migration45_46.java b/bramble-core/src/main/java/org/briarproject/bramble/db/Migration45_46.java
index 4cbbc05b0..598de9e6e 100644
--- a/bramble-core/src/main/java/org/briarproject/bramble/db/Migration45_46.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/db/Migration45_46.java
@@ -32,6 +32,7 @@ class Migration45_46 implements Migration<Connection> {
 			s = txn.createStatement();
 			s.execute("ALTER TABLE messages"
 					+ " ADD COLUMN temporary BOOLEAN DEFAULT FALSE NOT NULL");
+			s.close();
 		} catch (SQLException e) {
 			tryToClose(s, LOG, WARNING);
 			throw new DbException(e);
diff --git a/bramble-core/src/main/java/org/briarproject/bramble/db/Migration46_47.java b/bramble-core/src/main/java/org/briarproject/bramble/db/Migration46_47.java
index da14f5d36..f5abf198e 100644
--- a/bramble-core/src/main/java/org/briarproject/bramble/db/Migration46_47.java
+++ b/bramble-core/src/main/java/org/briarproject/bramble/db/Migration46_47.java
@@ -39,6 +39,7 @@ class Migration46_47 implements Migration<Connection> {
 			s.execute(dbTypes.replaceTypes("ALTER TABLE contacts"
 					+ " ADD COLUMN syncVersions"
 					+ " _BINARY DEFAULT '00' NOT NULL"));
+			s.close();
 		} catch (SQLException e) {
 			tryToClose(s, LOG, WARNING);
 			throw new DbException(e);