diff --git a/controller/tests/invoice.rs b/controller/tests/invoice.rs
index 70511d324..e637b4cf9 100644
--- a/controller/tests/invoice.rs
+++ b/controller/tests/invoice.rs
@@ -207,6 +207,45 @@ fn invoice_tx_impl(test_dir: &'static str) -> Result<(), libwallet::Error> {
 	let _ = test_framework::award_blocks_to_wallet(&chain, wallet1.clone(), mask1, 3, false);
 	//bh += 3;
 
+	// As above, but use owner API to finalize
+	let mut slate = Slate::blank(2, true);
+
+	wallet::controller::owner_single_use(Some(wallet2.clone()), mask2, None, |api, m| {
+		// Wallet 2 inititates an invoice transaction, requesting payment
+		let args = IssueInvoiceTxArgs {
+			amount: reward * 2,
+			..Default::default()
+		};
+		slate = api.issue_invoice_tx(m, args)?;
+		Ok(())
+	})?;
+	assert_eq!(slate.state, SlateState::Invoice1);
+
+	wallet::controller::owner_single_use(Some(wallet1.clone()), mask1, None, |api, m| {
+		// Wallet 1 receives the invoice transaction
+		let args = InitTxArgs {
+			src_acct_name: None,
+			amount: slate.amount,
+			minimum_confirmations: 2,
+			max_outputs: 500,
+			num_change_outputs: 1,
+			selection_strategy_is_use_all: true,
+			..Default::default()
+		};
+		slate = api.process_invoice_tx(m, &slate, args)?;
+		api.tx_lock_outputs(m, &slate)?;
+		Ok(())
+	})?;
+	assert_eq!(slate.state, SlateState::Invoice2);
+
+	// wallet 2 finalizes via owner API
+	wallet::controller::owner_single_use(Some(wallet2.clone()), mask2, None, |api, m| {
+		// Wallet 2 receives the invoice transaction
+		slate = api.finalize_tx(m, &slate)?;
+		Ok(())
+	})?;
+	assert_eq!(slate.state, SlateState::Invoice3);
+
 	// let logging finish
 	stopper.store(false, Ordering::Relaxed);
 	thread::sleep(Duration::from_millis(200));
diff --git a/libwallet/src/api_impl/foreign.rs b/libwallet/src/api_impl/foreign.rs
index be08950f4..315091cd4 100644
--- a/libwallet/src/api_impl/foreign.rs
+++ b/libwallet/src/api_impl/foreign.rs
@@ -15,7 +15,6 @@
 //! Generic implementation of owner API functions
 use strum::IntoEnumIterator;
 
-use crate::api_impl::owner::finalize_tx as owner_finalize;
 use crate::api_impl::owner::{check_ttl, post_tx};
 use crate::grin_core::core::FeeFields;
 use crate::grin_keychain::Keychain;
@@ -27,6 +26,8 @@ use crate::{
 	WalletBackend,
 };
 
+use super::owner::tx_lock_outputs;
+
 const FOREIGN_API_VERSION: u16 = 2;
 
 /// Return the version info
@@ -144,10 +145,9 @@ where
 	K: Keychain + 'a,
 {
 	let mut sl = slate.clone();
-	let context = w.get_private_context(keychain_mask, sl.id.as_bytes())?;
+	let mut context = w.get_private_context(keychain_mask, sl.id.as_bytes())?;
+	check_ttl(w, &sl)?;
 	if sl.state == SlateState::Invoice2 {
-		check_ttl(w, &sl)?;
-
 		// Add our contribution to the offset
 		sl.adjust_offset(&w.keychain(keychain_mask)?, &context)?;
 
@@ -165,8 +165,66 @@ where
 		}
 		sl.state = SlateState::Invoice3;
 		sl.amount = 0;
+	} else if sl.state == SlateState::Standard2 {
+		let keychain = w.keychain(keychain_mask)?;
+		let parent_key_id = w.parent_key_id();
+
+		if let Some(args) = context.late_lock_args.take() {
+			// Transaction was late locked, select inputs+change now
+			// and insert into original context
+
+			let current_height = w.w2n_client().get_chain_tip()?.0;
+			let mut temp_sl =
+				tx::new_tx_slate(&mut *w, context.amount, false, 2, false, args.ttl_blocks)?;
+			let temp_context = selection::build_send_tx(
+				w,
+				&keychain,
+				keychain_mask,
+				&mut temp_sl,
+				current_height,
+				args.minimum_confirmations,
+				args.max_outputs as usize,
+				args.num_change_outputs as usize,
+				args.selection_strategy_is_use_all,
+				Some(context.fee.map(|f| f.fee()).unwrap_or(0)),
+				parent_key_id.clone(),
+				false,
+				true,
+				false,
+			)?;
+
+			// Add inputs and outputs to original context
+			context.input_ids = temp_context.input_ids;
+			context.output_ids = temp_context.output_ids;
+
+			// Store the updated context
+			{
+				let mut batch = w.batch(keychain_mask)?;
+				batch.save_private_context(sl.id.as_bytes(), &context)?;
+				batch.commit()?;
+			}
+
+			// Now do the actual locking
+			tx_lock_outputs(w, keychain_mask, &sl)?;
+		}
+
+		// Add our contribution to the offset
+		sl.adjust_offset(&keychain, &context)?;
+
+		selection::repopulate_tx(&mut *w, keychain_mask, &mut sl, &context, true)?;
+
+		tx::complete_tx(&mut *w, keychain_mask, &mut sl, &context)?;
+		tx::verify_slate_payment_proof(&mut *w, keychain_mask, &parent_key_id, &context, &sl)?;
+		tx::update_stored_tx(&mut *w, keychain_mask, &context, &sl, false)?;
+		{
+			let mut batch = w.batch(keychain_mask)?;
+			batch.delete_private_context(sl.id.as_bytes())?;
+			batch.commit()?;
+		}
+		sl.state = SlateState::Standard3;
+		sl.amount = 0;
 	} else {
-		sl = owner_finalize(w, keychain_mask, slate)?;
+		return Err(Error::SlateState);
 	}
 	if post_automatically {
 		post_tx(w.w2n_client(), sl.tx_or_err()?, true)?;
diff --git a/libwallet/src/api_impl/owner.rs b/libwallet/src/api_impl/owner.rs
index 0ab87e47d..9563a5a8f 100644
--- a/libwallet/src/api_impl/owner.rs
+++ b/libwallet/src/api_impl/owner.rs
@@ -16,6 +16,7 @@
 
 use uuid::Uuid;
 
+use crate::api_impl::foreign::finalize_tx as foreign_finalize;
 use crate::grin_core::core::hash::Hashed;
 use crate::grin_core::core::{Output, OutputFeatures, Transaction};
 use crate::grin_core::libtx::proof;
@@ -807,68 +808,7 @@ where
 	C: NodeClient + 'a,
 	K: Keychain + 'a,
 {
-	let mut sl = slate.clone();
-	check_ttl(w, &sl)?;
-	let mut context = w.get_private_context(keychain_mask, sl.id.as_bytes())?;
-	let keychain = w.keychain(keychain_mask)?;
-	let parent_key_id = w.parent_key_id();
-
-	if let Some(args) = context.late_lock_args.take() {
-		// Transaction was late locked, select inputs+change now
-		// and insert into original context
-
-		let current_height = w.w2n_client().get_chain_tip()?.0;
-		let mut temp_sl =
-			tx::new_tx_slate(&mut *w, context.amount, false, 2, false, args.ttl_blocks)?;
-		let temp_context = selection::build_send_tx(
-			w,
-			&keychain,
-			keychain_mask,
-			&mut temp_sl,
-			current_height,
-			args.minimum_confirmations,
-			args.max_outputs as usize,
-			args.num_change_outputs as usize,
-			args.selection_strategy_is_use_all,
-			Some(context.fee.map(|f| f.fee()).unwrap_or(0)),
-			parent_key_id.clone(),
-			false,
-			true,
-			false,
-		)?;
-
-		// Add inputs and outputs to original context
-		context.input_ids = temp_context.input_ids;
-		context.output_ids = temp_context.output_ids;
-
-		// Store the updated context
-		{
-			let mut batch = w.batch(keychain_mask)?;
-			batch.save_private_context(sl.id.as_bytes(), &context)?;
-			batch.commit()?;
-		}
-
-		// Now do the actual locking
-		tx_lock_outputs(w, keychain_mask, &sl)?;
-	}
-
-	// Add our contribution to the offset
-	sl.adjust_offset(&keychain, &context)?;
-
-	selection::repopulate_tx(&mut *w, keychain_mask, &mut sl, &context, true)?;
-
-	tx::complete_tx(&mut *w, keychain_mask, &mut sl, &context)?;
-	tx::verify_slate_payment_proof(&mut *w, keychain_mask, &parent_key_id, &context, &sl)?;
-	tx::update_stored_tx(&mut *w, keychain_mask, &context, &sl, false)?;
-	{
-		let mut batch = w.batch(keychain_mask)?;
-		batch.delete_private_context(sl.id.as_bytes())?;
-		batch.commit()?;
-	}
-	sl.state = SlateState::Standard3;
-	sl.amount = 0;
-
-	Ok(sl)
+	foreign_finalize(w, keychain_mask, slate, false)
 }
 
 /// cancel tx
diff --git a/libwallet/src/error.rs b/libwallet/src/error.rs
index dc5735ae2..3ac0bc946 100644
--- a/libwallet/src/error.rs
+++ b/libwallet/src/error.rs
@@ -189,6 +189,10 @@ pub enum Error {
 	#[error("Can't Deserialize slate")]
 	SlateDeser,
 
+	/// Invalid slate state
+	#[error("Invalid slate state")]
+	SlateState,
+
 	/// Can't serialize slate pack
 	#[error("Can't Serialize slatepack")]
 	SlatepackSer,