diff --git a/setup/config/config_userapi.go b/setup/config/config_userapi.go
index 3c27a03d8..355d02d8a 100644
--- a/setup/config/config_userapi.go
+++ b/setup/config/config_userapi.go
@@ -45,8 +45,10 @@ func (c *UserAPI) Defaults() {
 	c.InternalAPI.Connect = "http://localhost:7781"
 	c.AccountDatabase.Defaults(10)
 	c.DeviceDatabase.Defaults(10)
+	c.ThreepidDatabase.Defaults(10)
 	c.AccountDatabase.ConnectionString = "file:userapi_accounts.db"
 	c.DeviceDatabase.ConnectionString = "file:userapi_devices.db"
+	c.ThreepidDatabase.ConnectionString = "file:userapi_threepids.db"
 	c.BCryptCost = bcrypt.DefaultCost
 	c.OpenIDTokenLifetimeMS = DefaultOpenIDTokenLifetimeMS
 }
@@ -56,5 +58,6 @@ func (c *UserAPI) Verify(configErrs *ConfigErrors, isMonolith bool) {
 	checkURL(configErrs, "user_api.internal_api.connect", string(c.InternalAPI.Connect))
 	checkNotEmpty(configErrs, "user_api.account_database.connection_string", string(c.AccountDatabase.ConnectionString))
 	checkNotEmpty(configErrs, "user_api.device_database.connection_string", string(c.DeviceDatabase.ConnectionString))
+	checkNotEmpty(configErrs, "user_api.threepid_database.connection_string", string(c.ThreepidDatabase.ConnectionString))
 	checkPositive(configErrs, "user_api.openid_token_lifetime_ms", c.OpenIDTokenLifetimeMS)
 }