diff --git a/packages/common-utils/CHANGELOG.md b/packages/common-utils/CHANGELOG.md
index 533fd37..004c54c 100644
--- a/packages/common-utils/CHANGELOG.md
+++ b/packages/common-utils/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+## Added
+
+- Property `waited` in `AsyncTransaction` to get a `Promise<Transaction>`
+
 ## 0.0.1-1 2025-02-17
 
 Initial release
diff --git a/packages/common-utils/src/asyncTransaction.ts b/packages/common-utils/src/asyncTransaction.ts
index a8e476a..e6b2605 100644
--- a/packages/common-utils/src/asyncTransaction.ts
+++ b/packages/common-utils/src/asyncTransaction.ts
@@ -12,6 +12,7 @@ export type AsyncTransaction<
 > & {
   decodedCall: Promise<Transaction<Arg, Pallet, Name, Asset>["decodedCall"]>
   getEncodedData: () => Promise<Binary>
+  waited: Promise<Transaction<Arg, Pallet, Name, Asset>>
 }
 
 export const wrapAsyncTx = <
@@ -23,6 +24,12 @@ export const wrapAsyncTx = <
   fn: () => Promise<Transaction<Arg, Pallet, Name, Asset>>,
 ): AsyncTransaction<Arg, Pallet, Name, Asset> => {
   const promise = fn()
+
+  // Prevent some runtimes from terminating for an uncaught exception
+  promise.catch((ex) => {
+    console.error(ex)
+  })
+
   return {
     sign: (...args) => promise.then((tx) => tx.sign(...args)),
     signSubmitAndWatch: (...args) =>
@@ -34,5 +41,6 @@ export const wrapAsyncTx = <
       promise.then((tx) => tx.getPaymentInfo(...args)),
     decodedCall: promise.then((tx) => tx.decodedCall),
     getEncodedData: () => promise.then((tx) => tx.getEncodedData()),
+    waited: promise,
   }
 }
diff --git a/packages/sdk-multisig/.papi/descriptors/.gitignore b/packages/sdk-multisig/.papi/descriptors/.gitignore
new file mode 100644
index 0000000..557cc81
--- /dev/null
+++ b/packages/sdk-multisig/.papi/descriptors/.gitignore
@@ -0,0 +1,3 @@
+*
+!.gitignore
+!package.json
diff --git a/packages/sdk-multisig/.papi/descriptors/package.json b/packages/sdk-multisig/.papi/descriptors/package.json
new file mode 100644
index 0000000..69a7d46
--- /dev/null
+++ b/packages/sdk-multisig/.papi/descriptors/package.json
@@ -0,0 +1,24 @@
+{
+  "version": "0.1.0-autogenerated.237886621120070658",
+  "name": "@polkadot-api/descriptors",
+  "files": [
+    "dist"
+  ],
+  "exports": {
+    ".": {
+      "types": "./dist/index.d.ts",
+      "module": "./dist/index.mjs",
+      "import": "./dist/index.mjs",
+      "require": "./dist/index.js"
+    },
+    "./package.json": "./package.json"
+  },
+  "main": "./dist/index.js",
+  "module": "./dist/index.mjs",
+  "browser": "./dist/index.mjs",
+  "types": "./dist/index.d.ts",
+  "sideEffects": false,
+  "peerDependencies": {
+    "polkadot-api": ">=1.11.2"
+  }
+}
diff --git a/packages/sdk-multisig/.papi/metadata/dot.scale b/packages/sdk-multisig/.papi/metadata/dot.scale
new file mode 100644
index 0000000..89ec73b
Binary files /dev/null and b/packages/sdk-multisig/.papi/metadata/dot.scale differ
diff --git a/packages/sdk-multisig/.papi/metadata/moonbeam.scale b/packages/sdk-multisig/.papi/metadata/moonbeam.scale
new file mode 100644
index 0000000..c7e9215
Binary files /dev/null and b/packages/sdk-multisig/.papi/metadata/moonbeam.scale differ
diff --git a/packages/sdk-multisig/.papi/polkadot-api.json b/packages/sdk-multisig/.papi/polkadot-api.json
new file mode 100644
index 0000000..4e864be
--- /dev/null
+++ b/packages/sdk-multisig/.papi/polkadot-api.json
@@ -0,0 +1,21 @@
+{
+  "version": 0,
+  "descriptorPath": ".papi/descriptors",
+  "options": {
+    "noDescriptorsPackage": true
+  },
+  "entries": {
+    "dot": {
+      "chain": "polkadot",
+      "metadata": ".papi/metadata/dot.scale",
+      "genesis": "0x91b171bb158e2d3848fa23a9f1c25182fb8e20313b2c1eb49219da7a70ce90c3",
+      "codeHash": "0x0627ae9ae2a8d0de99a7dad056136f855f32f82391c48bf8a531506fe231a42b"
+    },
+    "moonbeam": {
+      "wsUrl": "wss://moonbeam-rpc.dwellir.com",
+      "metadata": ".papi/metadata/moonbeam.scale",
+      "genesis": "0xfe58ea77779b7abda7da4ec526d14db9b1e9cd40a217c34892af80a9b332b76d",
+      "codeHash": "0x802c6b285502245d97dc73bdb164c128b9c7794637c67a3f23a105327d5566d2"
+    }
+  }
+}
diff --git a/packages/sdk-multisig/.papi/whitelist.ts b/packages/sdk-multisig/.papi/whitelist.ts
new file mode 100644
index 0000000..cd90bb2
--- /dev/null
+++ b/packages/sdk-multisig/.papi/whitelist.ts
@@ -0,0 +1,9 @@
+import type { DotWhitelistEntry } from "./descriptors"
+
+export const whitelist: DotWhitelistEntry[] = [
+  "query.Multisig.Multisigs",
+  "tx.Multisig.as_multi_threshold_1",
+  "tx.Multisig.as_multi",
+  "tx.Multisig.approve_as_multi",
+  "api.TransactionPaymentApi.query_info",
+]
diff --git a/packages/sdk-multisig/CHANGELOG.md b/packages/sdk-multisig/CHANGELOG.md
new file mode 100644
index 0000000..f6efa27
--- /dev/null
+++ b/packages/sdk-multisig/CHANGELOG.md
@@ -0,0 +1,5 @@
+# Changelog
+
+## Unreleased
+
+Initial release
diff --git a/packages/sdk-multisig/README.md b/packages/sdk-multisig/README.md
new file mode 100644
index 0000000..054dae4
--- /dev/null
+++ b/packages/sdk-multisig/README.md
@@ -0,0 +1 @@
+# @polkadot-api/sdk-multisig
diff --git a/packages/sdk-multisig/package.json b/packages/sdk-multisig/package.json
new file mode 100644
index 0000000..0e5d101
--- /dev/null
+++ b/packages/sdk-multisig/package.json
@@ -0,0 +1,55 @@
+{
+  "name": "@polkadot-api/sdk-multisig",
+  "version": "0.0.1",
+  "sideEffects": false,
+  "author": "Victor Oliva (https://github.com/voliva)",
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/polkadot-api/papi-sdks.git"
+  },
+  "exports": {
+    ".": {
+      "node": {
+        "production": {
+          "import": "./dist/esm/src/index.mjs",
+          "require": "./dist/index.js",
+          "default": "./dist/index.js"
+        },
+        "import": "./dist/esm/src/index.mjs",
+        "require": "./dist/index.js",
+        "default": "./dist/index.js"
+      },
+      "module": "./dist/esm/src/index.mjs",
+      "import": "./dist/esm/src/index.mjs",
+      "require": "./dist/index.js",
+      "default": "./dist/index.js"
+    },
+    "./package.json": "./package.json"
+  },
+  "main": "./dist/index.js",
+  "module": "./dist/esm/src/index.mjs",
+  "browser": "./dist/esm/src/index.mjs",
+  "types": "./dist/index.d.ts",
+  "files": [
+    "dist"
+  ],
+  "scripts": {
+    "build": "papi generate --whitelist .papi/whitelist.ts && mv .papi/descriptors/dist/index.mjs .papi/descriptors/dist/index.js && tsc --noEmit && rollup -c ../../rollup.config.js",
+    "lint": "prettier --check README.md \"src/**/*.{js,jsx,ts,tsx,json,md}\"",
+    "format": "prettier --write README.md \"src/**/*.{js,jsx,ts,tsx,json,md}\"",
+    "prepack": "pnpm run build"
+  },
+  "license": "MIT",
+  "dependencies": {
+    "@polkadot-api/common-sdk-utils": "workspace:*",
+    "@polkadot-api/substrate-bindings": "^0.16.3"
+  },
+  "peerDependencies": {
+    "polkadot-api": ">=1.14.1",
+    "rxjs": ">=7.8.0"
+  },
+  "devDependencies": {
+    "polkadot-api": "^1.14.1",
+    "rxjs": "^7.8.2"
+  }
+}
diff --git a/packages/sdk-multisig/src/index.ts b/packages/sdk-multisig/src/index.ts
new file mode 100644
index 0000000..a77e0b5
--- /dev/null
+++ b/packages/sdk-multisig/src/index.ts
@@ -0,0 +1,2 @@
+export { createMultisigSdk } from "./multisig-sdk"
+export type { MultisigSdk } from "./sdk-types"
diff --git a/packages/sdk-multisig/src/multisig-sdk.ts b/packages/sdk-multisig/src/multisig-sdk.ts
new file mode 100644
index 0000000..950da29
--- /dev/null
+++ b/packages/sdk-multisig/src/multisig-sdk.ts
@@ -0,0 +1,193 @@
+import { wrapAsyncTx } from "@polkadot-api/common-sdk-utils"
+import {
+  Binary,
+  Blake2256,
+  getMultisigAccountId,
+  getSs58AddressInfo,
+  HexString,
+  sortMultisigSignatories,
+  SS58String,
+} from "@polkadot-api/substrate-bindings"
+import { AccountId, Transaction } from "polkadot-api"
+import { fromHex, toHex } from "polkadot-api/utils"
+import { dot, moonbeam } from "../.papi/descriptors/dist"
+import { CreateMultisigSdk, MultisigSdk, MultisigTxOptions } from "./sdk-types"
+
+const defaultMultisigTxOptions: MultisigTxOptions<unknown> = {
+  method: (approvals, threshold) =>
+    approvals.length === threshold - 1 ? "as_multi" : "approve_as_multi",
+}
+
+export const createMultisigSdk: CreateMultisigSdk = (client, addrType) => {
+  type Addr = typeof addrType extends "acc20" ? HexString : SS58String
+  const isAddr20 = addrType === "acc20"
+
+  const ss58Api = client.getTypedApi(dot)
+  const addr20Api = client.getTypedApi(moonbeam)
+  const activeApi = isAddr20 ? addr20Api : ss58Api
+
+  const toSS58 = AccountId().dec
+
+  const getMultisigTx: MultisigSdk<Addr>["getMultisigTx"] = (
+    multisig,
+    signatory,
+    txOrCallData,
+    options,
+  ) => {
+    options = {
+      ...defaultMultisigTxOptions,
+      ...options,
+    }
+
+    const toAddress = (value: Uint8Array): Addr => {
+      if (isAddr20) {
+        return toHex(value) as Addr
+      }
+      return toSS58(value) as Addr
+    }
+
+    const pubKeys = sortMultisigSignatories(
+      multisig.signatories.map(getPublicKey),
+    )
+    const multisigId = getMultisigAccountId({
+      threshold: multisig.threshold,
+      signatories: pubKeys,
+    })
+
+    const signatoryId = getPublicKey(signatory)
+    const otherSignatories = pubKeys.filter(
+      (addr) => !u8ArrEq(addr, signatoryId),
+    )
+    if (otherSignatories.length === multisig.signatories.length) {
+      throw new Error("Signer is not one of the signatories of the multisig")
+    }
+
+    return wrapAsyncTx(async () => {
+      const [tx, callData] =
+        "getEncodedData" in txOrCallData
+          ? [txOrCallData, await txOrCallData.getEncodedData()]
+          : [await activeApi.txFromCallData(txOrCallData), txOrCallData]
+
+      if (multisig.threshold === 1) {
+        return activeApi.tx.Multisig.as_multi_threshold_1({
+          other_signatories: otherSignatories.map(toAddress),
+          call: tx.decodedCall,
+        })
+      }
+
+      const callHash = Blake2256(callData.asBytes())
+      const [multisigInfo, weightInfo] = await Promise.all([
+        activeApi.query.Multisig.Multisigs.getValue(
+          toAddress(multisigId),
+          Binary.fromBytes(callHash),
+        ),
+        tx.getPaymentInfo(signatoryId),
+      ])
+
+      if (
+        multisigInfo?.approvals.some((approval) =>
+          u8ArrEq(getPublicKey(approval), signatoryId),
+        )
+      ) {
+        throw new Error("Multisig call already approved by signer")
+      }
+
+      const method = options.method(
+        multisigInfo?.approvals ?? [],
+        multisig.threshold,
+      )
+
+      const commonPayload = {
+        threshold: multisig.threshold,
+        other_signatories: otherSignatories.map(toAddress),
+        max_weight: weightInfo.weight,
+        maybe_timepoint: multisigInfo?.when,
+      }
+
+      const wrappedTx: Transaction<any, any, any, any> =
+        method === "approve_as_multi"
+          ? activeApi.tx.Multisig.approve_as_multi({
+              ...commonPayload,
+              call_hash: Binary.fromBytes(callHash),
+            })
+          : activeApi.tx.Multisig.as_multi({
+              ...commonPayload,
+              call: tx.decodedCall,
+            })
+
+      return wrappedTx
+    })
+  }
+
+  return {
+    getMultisigTx,
+    getMultisigSigner(multisig, signer, options) {
+      const pubKeys = sortMultisigSignatories(
+        multisig.signatories.map(getPublicKey),
+      )
+      const multisigId = getMultisigAccountId({
+        threshold: multisig.threshold,
+        signatories: pubKeys,
+      })
+
+      const toAddress = (value: Uint8Array): Addr => {
+        if (multisig.signatories[0].startsWith("0x")) {
+          return toHex(value) as Addr
+        }
+        return toSS58(value) as Addr
+      }
+
+      const signerId =
+        "accountId" in signer
+          ? (signer.accountId as Uint8Array)
+          : signer.publicKey
+
+      return {
+        publicKey: signer.publicKey,
+        accountId: multisigId,
+        signBytes() {
+          throw new Error("Raw bytes can't be signed with a multisig")
+        },
+        async signTx(
+          callData,
+          signedExtensions,
+          metadata,
+          atBlockNumber,
+          hasher,
+        ) {
+          const tx = await activeApi.txFromCallData(Binary.fromBytes(callData))
+          const wrappedTx = getMultisigTx(
+            multisig,
+            toAddress(signerId),
+            tx,
+            options,
+          )
+
+          return signer.signTx(
+            (await wrappedTx.getEncodedData()).asBytes(),
+            signedExtensions,
+            metadata,
+            atBlockNumber,
+            hasher,
+          )
+        },
+      }
+    },
+  }
+}
+
+const u8ArrEq = (a: Uint8Array, b: Uint8Array) => {
+  if (a.length !== b.length) return false
+  return a.every((v, i) => v === b[i])
+}
+
+const getPublicKey = (addr: SS58String | HexString) => {
+  if (addr.startsWith("0x")) {
+    return fromHex(addr)
+  }
+  const info = getSs58AddressInfo(addr)
+  if (!info.isValid) {
+    throw new Error(`Invalid SS58 address ${addr}`)
+  }
+  return info.publicKey
+}
diff --git a/packages/sdk-multisig/src/sdk-types.ts b/packages/sdk-multisig/src/sdk-types.ts
new file mode 100644
index 0000000..34c22db
--- /dev/null
+++ b/packages/sdk-multisig/src/sdk-types.ts
@@ -0,0 +1,42 @@
+import { AsyncTransaction } from "@polkadot-api/common-sdk-utils"
+import {
+  Binary,
+  HexString,
+  PolkadotClient,
+  PolkadotSigner,
+  SS58String,
+  Transaction,
+} from "polkadot-api"
+
+export interface MultisigAccount<Addr> {
+  signatories: Addr[]
+  threshold: number
+}
+
+export interface MultisigTxOptions<Addr> {
+  method: (
+    approvals: Array<Addr>,
+    threshold: number,
+  ) => "as_multi" | "approve_as_multi"
+}
+
+export interface CreateMultisigSdk {
+  <AType extends "ss58" | "acc20" = "ss58">(
+    client: PolkadotClient,
+    addrType?: AType,
+  ): MultisigSdk<AType extends "acc20" ? HexString : SS58String>
+}
+
+export interface MultisigSdk<Addr> {
+  getMultisigTx(
+    multisig: MultisigAccount<Addr>,
+    signatory: Addr,
+    txOrCallData: Transaction<any, any, any, any> | Binary,
+    options?: MultisigTxOptions<Addr>,
+  ): AsyncTransaction<any, any, any, any>
+  getMultisigSigner(
+    multisig: MultisigAccount<Addr>,
+    signer: PolkadotSigner,
+    options?: MultisigTxOptions<Addr>,
+  ): PolkadotSigner
+}
diff --git a/packages/sdk-multisig/tsconfig.json b/packages/sdk-multisig/tsconfig.json
new file mode 100644
index 0000000..73f9f03
--- /dev/null
+++ b/packages/sdk-multisig/tsconfig.json
@@ -0,0 +1,12 @@
+{
+  "extends": "../../tsconfig.base",
+  "include": ["src", "tests"],
+  "compilerOptions": {
+    "baseUrl": "src",
+    "resolveJsonModule": true,
+    "skipLibCheck": true,
+    "paths": {
+      "@/*": ["*"]
+    }
+  }
+}
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 2412e32..4f8b7ad 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -183,6 +183,22 @@ importers:
         specifier: ^7.8.2
         version: 7.8.2
 
+  packages/sdk-multisig:
+    dependencies:
+      '@polkadot-api/common-sdk-utils':
+        specifier: workspace:*
+        version: link:../common-utils
+      '@polkadot-api/substrate-bindings':
+        specifier: ^0.16.3
+        version: 0.16.3
+    devDependencies:
+      polkadot-api:
+        specifier: ^1.14.1
+        version: 1.18.0(postcss@8.5.6)(rxjs@7.8.2)
+      rxjs:
+        specifier: ^7.8.2
+        version: 7.8.2
+
   packages/sdk-remote-proxy:
     dependencies:
       '@polkadot-api/meta-signers':