Over 9% yield! I'll be kicking myself if I don't buy these 2 FTSE stocks coming in September

I FTSE 100 is up more than 12% over the past year but is still loaded with high-value income stocks, many of which offer high dividend yields.

The two green chips yield more than 9% a year, crushing returns on cash or bonds. Although the benefits are never guaranteed, I think they may be sustainable. I own both stocks and am willing to buy more before they go ex-dividend on September 26th.

An insurance conglomerate Phoenix Group Holdings share price (LSE: PHNX) offers the highest trailing yield across the index at 9.36%. And it has an excellent track record of increasing shareholder payouts, year after year, as this table shows.

Chart with TradingView

Does Phoenix pay dividends?

In order to finance this major shareholder, the company needs to generate lots of cash. Thankfully, Phoenix has been doing well in this regard, hitting its targets of hitting £2bn last year.

The share price will never go up but it increased by 4.34% in August. Over one year, it increased by 10.02%. OK so it's not easy Nvidia-style growth , but throw in the yield and I'm looking at a potential return of around 20% per year.

Phoenix must work hard to continue to deliver sales and cash flow, as it operates in a mature and competitive UK insurance market. There are new growth opportunities emerging, especially in bulk annuities, but they are not the only ones they are chasing.

Trading at 17.3 times earnings, the shares are not very cheap. That's just above the FTSE 100's P/E ratio of 15.3 times. However, I think there is a real opportunity here. As interest rates are lowered, income from cash and bonds will inevitably decline. That will make a high yield like this seem more attractive.

The same goes for my second top income pick for September, the wealth manager IM&G (LSE: MNG). paid a dividend of 9.19 %.

Can M&G afford its sky-high dividend too?

When M&G's final dividend arrived in my trading account on May 13th, I knew about it. My 3,289 shares paid me £406.77, which I reinvested back into the stock, thus acquiring a further 196 M&G shares. They will pay me dividends again, in the future, and I will reinvest every penny to build my stake.

The downside is that I don't expect rapid growth in the budget going forward, as M&G has increased the 2023 payout by a slight 0.1p to 19.7p. Let's see what the chart says.

Chart with TradingView

M&G's share price is actually up 12.93% over the past year, so again, I'm aiming for a 12-month total return of over 20%. Shares underperformed as the group was kicked out of insurance Prudential in 2019, but I hope for better days when economic and stock market sentiment improves.

Also, M&G shares were cheap when I bought them. Today they trade at 16.8 times earnings, just above the FTSE 100 average. That won't stop me from buying them. I just need to get the money together before they leave on September 26th. Otherwise I'll be kicking myself for missing out on other benefits.