The most attractive rate on offer is from the 18-month bond which pays 3%.
However, you will need a whopping £200,000 deposit to get access to this top tier rate and also be either a 123 Current Account or a 123 Credit Card holder to apply.
Dramatic tier system
The minimum deposit on each of Santander's new bonds is only £500. However, it's the second level tiers that offer the best rates, but that requires a jump in investment to at least £200,000.
That's a big gulf in deposit size but thankfully the rates don't follow this sharp pattern.
Existing 123 customers with a modest £500 to invest get access to a rate of 2.3% on the one-year bond, 2.9% on the 18-month bond and 2.5% on the two-year bond.
In contrast 123 existing customers with £200,000 or more to deposit get access to a rate of 2.4% on the one-year bond, 3% on the 18-month term and 2.6% on the two-year alternative.
That's only a 0.1% difference for investing a very large sum of money!
Beware the top tier
Although Santander's top tier rates are inviting, you shouldn't put all your eggs in one basket.
The Financial Services Compensation Scheme will only cover a maximum of £85,000 per account so depositing £200,000 with one of the new bonds from Santander is a potentially risky idea, should the bank collapse.
If you're lucky enough to have a large amount of money and need a safe home for it, you would be better off splitting up the total and dividing the pots between several accounts to ensure the safety of your nest egg.
Falling bond rates
Savers have had a tough time recently as rates across all types of accounts have plummeted over the last year.
According to financial information website, Moneyfacts, the average one-year bond now pays just 2.18% (down from 2.77% last year) and the average two-year bond now pays 2.49% (down from 3.32% last year).
The Santander trio offers slightly better than the average right now but there are better rates out there that don't require you to be an existing customer.
The top one-year fixed rate bond at the moment comes from United Bank and pays 2.75% for those with at least £2,000 to invest.
But if you are prepared to lock your money away for longer, the top two-year deal pays 3.05% and comes from FirstSave for those that have a minimum of £1,000 to deposit.
For those in search of some middle ground, the best 18-month bond comes from GE Capital. It pays 2.9% like Santander's 18-month offering but is not limited to existing customers. You do however have to have a slightly higher minimum deposit of £1,000.
The best in-betweener bonds
Personally I like the sound of the 18-month bond as for sacrificing a bit of time but not locking in for too long you get a good rate.
Here are the best bonds that last longer than a year but less than two years. For a comprehensive round-up of the best fixed rate bonds across all terms check out: The top fixed rate savings bonds.
Does loyalty pay?
The 18-month bond from Santander could have been a market leader, with a rate of 2.9% and a small deposit of £500, were it not for the existing customer proviso.
But is it worth becoming a 123 customer to get access to these rates?
Santander's 123 schemes reward customers with cashback. The 123 Credit Card pays tiered levels of cashback on certain types of spending. You can get 1% back on what you buy in supermarkets, 2% for shopping in department stores and 3% on travel spends like petrol or rail tickets.
The downside is that you will need to pay a £24 annual fee for the privilege.
The new Santander 123 Current Account, launched in March, is also very rewarding. It's a unique account which pays tiered cashback on direct debits and regular spends as well as credit interest on balances up to £20,000. You can get 1% on council tax and water bills as well as payments you make if you have a Santander mortgage, 2% on electricity and gas bills and 3% on communication bills like broadband. But this account also comes with a annual fee of £24.
In this instance loyalty can pay but elsewhere this concept doesn't always stick.