diff --git a/src/db.rs b/src/db.rs
index 3eddc1f..14e70b0 100644
--- a/src/db.rs
+++ b/src/db.rs
@@ -22,6 +22,7 @@ pub(crate) trait DBConnection {
     fn set_invoice_state(&self, invoice: Invoice, s: i32) -> anyhow::Result<()>;
     fn get_user_by_name(&self, name: String) -> anyhow::Result<Option<AppUser>>;
     fn get_user_by_id(&self, id: i32) -> anyhow::Result<Option<AppUser>>;
+    fn get_user_by_pubkey(&self, pubkey: String) -> anyhow::Result<Option<AppUser>>;
     fn get_user_and_increment_counter(&self, name: &str) -> anyhow::Result<Option<AppUser>>;
     fn insert_new_zap(&self, new_zap: Zap) -> anyhow::Result<Zap>;
     fn get_zap_by_id(&self, id: i32) -> anyhow::Result<Option<Zap>>;
@@ -71,6 +72,11 @@ impl DBConnection for PostgresConnection {
         AppUser::get_by_name(conn, name)
     }
 
+    fn get_user_by_pubkey(&self, pubkey: String) -> anyhow::Result<Option<AppUser>> {
+        let conn = &mut self.db.get()?;
+        AppUser::get_by_pubkey(conn, pubkey)
+    }
+
     fn get_user_by_id(&self, id: i32) -> anyhow::Result<Option<AppUser>> {
         let conn = &mut self.db.get()?;
         AppUser::get_by_id(conn, id)
diff --git a/src/main.rs b/src/main.rs
index d1ba5b2..924c1d0 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -17,8 +17,9 @@ use crate::{
     invoice::handle_pending_invoices,
     mint::{setup_multimint, MultiMintWrapperTrait},
     routes::{
-        check_pubkey, check_username, health_check, lnurl_callback_route, lnurl_verify_route,
-        register_route, root, validate_cors, well_known_lnurlp_route, well_known_nip5_route,
+        check_pubkey, check_registration_info, check_username, health_check, lnurl_callback_route,
+        lnurl_verify_route, register_route, root, validate_cors, well_known_lnurlp_route,
+        well_known_nip5_route,
     },
 };
 
@@ -168,7 +169,8 @@ async fn main() -> anyhow::Result<()> {
         .route("/", get(root))
         .route("/health-check", get(health_check))
         .route("/v1/check-username/:username", get(check_username))
-        .route("/v1/check-pubkey/:pubkey", get(check_pubkey))
+        .route("/v1/check-pubkey/:pubkey", get(check_pubkey)) // DEPRECATED for check-registration
+        .route("/v1/check-registration", post(check_registration_info))
         .route("/v1/register", post(register_route))
         .route("/.well-known/nostr.json", get(well_known_nip5_route))
         .route(
diff --git a/src/register.rs b/src/register.rs
index 2e74570..884aa57 100644
--- a/src/register.rs
+++ b/src/register.rs
@@ -1,7 +1,7 @@
 use std::str::FromStr;
 
 use crate::{
-    models::app_user::NewAppUser,
+    models::app_user::{AppUser, NewAppUser},
     routes::{RegisterRequest, RegisterResponse},
     State,
 };
@@ -35,6 +35,10 @@ pub fn check_registered_pubkey(state: &State, pubkey: String) -> anyhow::Result<
     state.db.check_registered_pubkey(pubkey)
 }
 
+pub fn get_user_by_pubkey(state: &State, pubkey: String) -> anyhow::Result<Option<AppUser>> {
+    state.db.get_user_by_pubkey(pubkey)
+}
+
 pub fn generate_random_name(state: &State) -> anyhow::Result<String> {
     loop {
         let new_name = Generator::with_naming(names::Name::Numbered)
diff --git a/src/routes.rs b/src/routes.rs
index 6245c33..12cacc7 100644
--- a/src/routes.rs
+++ b/src/routes.rs
@@ -1,7 +1,7 @@
 use crate::{
     lnurlp::{lnurl_callback, verify, well_known_lnurlp},
     nostr::well_known_nip5,
-    register::{check_available, check_registered_pubkey, register},
+    register::{check_available, check_registered_pubkey, get_user_by_pubkey, register},
     State, ALLOWED_LOCALHOST, ALLOWED_ORIGINS, ALLOWED_SUBDOMAIN, API_VERSION,
 };
 use axum::extract::{Path, Query};
@@ -13,6 +13,7 @@ use axum::{Json, TypedHeader};
 use fedimint_core::Amount;
 use fedimint_ln_common::lightning_invoice::Bolt11Invoice;
 use log::{error, info};
+use nostr::Event;
 use serde::{de, Deserialize, Deserializer, Serialize};
 use serde_json::{json, Value};
 use std::{collections::HashMap, fmt::Display, str::FromStr};
@@ -70,6 +71,54 @@ pub async fn check_pubkey(
     }
 }
 
+#[derive(Serialize, Deserialize, Clone)]
+pub struct RegistrationInfo {
+    pub name: Option<String>,
+    pub federation_id: Option<String>,
+}
+
+pub async fn check_registration_info(
+    origin: Option<TypedHeader<Origin>>,
+    Extension(state): Extension<State>,
+    Json(event): Json<Event>,
+) -> Result<Json<RegistrationInfo>, (StatusCode, String)> {
+    validate_cors(origin)?;
+
+    let pubkey = event.author();
+    info!("check_registration_info: {}", pubkey);
+
+    if event.verify().is_err() {
+        error!("error in check_registration_info: bad event");
+        return Err((StatusCode::BAD_REQUEST, "Bad event".to_string()));
+    }
+
+    // make sure it was made in the last 30 seconds
+    if event.created_at() < nostr::Timestamp::now() - 30_i64 {
+        error!("error in check_registration_info: event expired");
+        return Err((StatusCode::BAD_REQUEST, "Event expired".to_string()));
+    }
+
+    match get_user_by_pubkey(&state, pubkey.to_string()) {
+        Ok(Some(u)) => {
+            info!("check_pubkey finished: {}", pubkey);
+
+            Ok(Json(RegistrationInfo {
+                name: Some(u.name),
+                federation_id: Some(u.federation_id),
+            }))
+        }
+        Ok(None) => {
+            info!("check_pubkey not found: {}", pubkey);
+
+            Ok(Json(RegistrationInfo {
+                name: None,
+                federation_id: None,
+            }))
+        }
+        Err(e) => Err(handle_anyhow_error("check_pubkey", e)),
+    }
+}
+
 #[derive(Deserialize, Clone)]
 pub struct RegisterRequest {
     pub name: Option<String>,