17 Trade and other payables
| | 2015 | 2014 |
Trade payables | 2,814 | 948 |
Group companies Bouwinvest | 1 | 10,572 |
Rent invoiced in advance | 4,566 | 4,873 |
Tenant deposits | 363 | 1,079 |
Service charge payments | 1,141 | 774 |
Promotion costs | 34 | 117 |
Tax | 43 | 77 |
Other payables | 218 | 1,085 |
Balance as at 31 December | 9,180 | 19,525 |
The other payables relate to invoices yet to be received for maintenance of and investments in the portfolio.