Please follow the steps below.

  1. Open the mnemonic tool here:
  2. For greater security we recommend downloading the HTML file and performing this whole process while your device is offline.
  3. Select the coin you want from the dropdown box (BTC should be the default).
  4. Scroll down to the "Derivation path" section
  5. Select BIP44, BIP49 or BIP84 to get the key for your Legacy, Compatibility or Default wallets (read more below)
  6. Copy the Account Extended Private Key
  7. Go to Electrum and then File -> New/Restore -> Standard wallet -> Use a master key
  8. Paste your key obtained on step 6 and press next
  9. Set a password.

Coinomi is fully updated with Segwit support and works seamlessly with 3 types of addresses: Legacy (starting with "1"), Segwit compatibility (starting with "3") and default Segwit (starting with "bc1").  Each of those address types has its own master key. You should repeat steps 5 to 9 once for each format to see 100% of your balance in Electrum. Each time you spend from Coinomi, no matter which wallet you had coins in, the change will be sent to a Default (BIP84) address.