diff --git a/packages/backend/migration/1752377661219-UserPending-ip.js b/packages/backend/migration/1752377661219-UserPending-ip.js
new file mode 100644
index 0000000000..12e5d6cc3e
--- /dev/null
+++ b/packages/backend/migration/1752377661219-UserPending-ip.js
@@ -0,0 +1,14 @@
+/*
+ * SPDX-FileCopyrightText: наб and other Sharkey contributors
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+export class UserPendingIp1752377661219 {
+	async up(queryRunner) {
+		await queryRunner.query(`ALTER TABLE "user_pending" ADD "requestOriginIp" varchar(128)`);
+	}
+
+	async down(queryRunner) {
+		await queryRunner.query(`ALTER TABLE "user_pending" DROP COLUMN "requestOriginIp"`);
+	}
+}
diff --git a/packages/backend/src/models/UserPending.ts b/packages/backend/src/models/UserPending.ts
index 972c862a1a..2b4d5ac329 100644
--- a/packages/backend/src/models/UserPending.ts
+++ b/packages/backend/src/models/UserPending.ts
@@ -37,4 +37,10 @@ export class MiUserPending {
 		nullable: true,
 	})
 	public reason: string;
+
+	@Column('varchar', {
+		length: 128,
+		nullable: true,
+	})
+	public requestOriginIp: string | null;
 }
diff --git a/packages/backend/src/server/api/SignupApiService.ts b/packages/backend/src/server/api/SignupApiService.ts
index c1864ce959..86896264dd 100644
--- a/packages/backend/src/server/api/SignupApiService.ts
+++ b/packages/backend/src/server/api/SignupApiService.ts
@@ -7,7 +7,7 @@ import { Inject, Injectable } from '@nestjs/common';
 import * as argon2 from 'argon2';
 import { IsNull } from 'typeorm';
 import { DI } from '@/di-symbols.js';
-import type { RegistrationTicketsRepository, UsedUsernamesRepository, UserPendingsRepository, UserProfilesRepository, UsersRepository, MiRegistrationTicket, MiMeta } from '@/models/_.js';
+import type { RegistrationTicketsRepository, UsedUsernamesRepository, UserPendingsRepository, UserProfilesRepository, UsersRepository, MiRegistrationTicket, MiMeta, UserIpsRepository } from '@/models/_.js';
 import type { Config } from '@/config.js';
 import { CaptchaService } from '@/core/CaptchaService.js';
 import { IdService } from '@/core/IdService.js';
@@ -19,11 +19,14 @@ import { FastifyReplyError } from '@/misc/fastify-reply-error.js';
 import { bindThis } from '@/decorators.js';
 import { L_CHARS, secureRndstr } from '@/misc/secure-rndstr.js';
 import { RoleService } from '@/core/RoleService.js';
+import Logger from '@/logger.js';
+import { LoggerService } from '@/core/LoggerService.js';
 import { SigninService } from './SigninService.js';
 import type { FastifyRequest, FastifyReply } from 'fastify';
 
 @Injectable()
 export class SignupApiService {
+	private logger: Logger;
 	constructor(
 		@Inject(DI.config)
 		private config: Config,
@@ -46,6 +49,9 @@ export class SignupApiService {
 		@Inject(DI.registrationTicketsRepository)
 		private registrationTicketsRepository: RegistrationTicketsRepository,
 
+		@Inject(DI.userIpsRepository)
+		private userIpsRepository: UserIpsRepository,
+
 		private userEntityService: UserEntityService,
 		private idService: IdService,
 		private captchaService: CaptchaService,
@@ -53,7 +59,9 @@ export class SignupApiService {
 		private signinService: SigninService,
 		private emailService: EmailService,
 		private roleService: RoleService,
+		private loggerService: LoggerService,
 	) {
+		this.logger = this.loggerService.getLogger('Signup');
 	}
 
 	@bindThis
@@ -213,6 +221,7 @@ export class SignupApiService {
 				username: username,
 				password: hash,
 				reason: reason,
+				requestOriginIp: this.meta.enableIpLogging ? request.ip : null,
 			});
 
 			const link = `${this.config.url}/signup-complete/${code}`;
@@ -249,6 +258,10 @@ export class SignupApiService {
 				});
 			}
 
+			if (this.meta.enableIpLogging) {
+				this.logIp(request.ip, null, account.id);
+			}
+
 			const moderators = await this.roleService.getModerators();
 
 			for (const moderator of moderators) {
@@ -282,6 +295,10 @@ export class SignupApiService {
 					});
 				}
 
+				if (this.meta.enableIpLogging) {
+					this.logIp(request.ip, null, account.id);
+				}
+
 				return {
 					...res,
 					token: secret,
@@ -332,6 +349,15 @@ export class SignupApiService {
 				});
 			}
 
+			if (pendingUser.requestOriginIp) {
+				this.logIp(pendingUser.requestOriginIp, this.idService.parse(pendingUser.id).date, account.id);
+			}
+
+			// The sign-up request and the confirmation may've come from different addresses: log both
+			if (this.meta.enableIpLogging) {
+				this.logIp(request.ip, null, account.id);
+			}
+
 			if (this.meta.approvalRequiredForSignup) {
 				if (pendingUser.email) {
 					this.emailService.sendEmail(pendingUser.email, 'Approval pending',
@@ -359,4 +385,17 @@ export class SignupApiService {
 			throw new FastifyReplyError(400, String(err), err);
 		}
 	}
+
+	@bindThis
+	private logIp(ip: string, ipDate: Date | null, userId: MiLocalUser['id']) {
+		try {
+			this.userIpsRepository.createQueryBuilder().insert().values({
+				createdAt: ipDate ?? new Date(),
+				userId,
+				ip,
+			}).orIgnore(true).execute();
+		} catch (err) {
+			this.logger.error(err as Error);
+		}
+	}
 }